Oil-in-water emulsion composition using insect material and method for producing the same

Abstract

To provide an emulsion composition using a suitable raw material from the viewpoint of response to milk allergy and environmental response, and having excellent emulsion stability.SOLUTION: An oil-in-water emulsion composition according to an example comprises water, an oil, and solid particles, wherein the solid particles are present at the interface between the water and the oil, at least some of the solid particles are insect proteins, and the pH of an aqueous phase or an aqueous dispersion containing the solid particles is 7.5 or less. In another example, the surface tensions of the aqueous phases may be 32mN / m or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an emulsion composition and a method for producing the same, as well as to foods, milk substitutes, pharmaceuticals, cosmetics and personal care products containing the emulsion composition. [Background technology]

[0002] Surfactants have traditionally been used for emulsification in the food industry. However, because surfactant-based emulsification is thermodynamically unstable, it has been necessary to reduce the oil droplet size of oil-in-water emulsions (O / W emulsions) to the submicron level in order to ensure long-term stability and stability during sterilization processes at high temperatures.

[0003] In recent years, in the food industry, there has been an increasing need for an appearance that stimulates the appetite, flavor (stimulating the senses of taste and smell), texture, and attention to ingredients for health-conscious consumers. Therefore, there is a demand for the development of oil-in-water emulsions that have emulsion sizes and structures different from those of conventional emulsion compositions using surfactants.

[0004] On the other hand, with the increase in food allergy patients who develop allergies to food, the use of allergenic substances is sometimes restricted, and attention is being paid to the food ingredients used. Food allergies are highly dangerous, as they can cause serious symptoms such as itching and inflammation of the skin, and anaphylactic shock, which can lead to death. Therefore, for food applications, there is a demand for the provision of oil-in-water emulsions in which the allergenic substance in the food ingredients used is replaced with a different food ingredient, depending on the allergenic substance of the eater.

[0005] For example, when dealing with milk allergies, it is necessary to avoid milk-derived proteins as food ingredients, especially casein, which is highly allergenic, and the whey protein β-lactoglobulin. Soybean-derived proteins are also known to be allergenic substances. Other allergens include proteins derived from peanuts and nuts such as walnuts and almonds.

[0006] In providing an emulsion composition, it is known that emulsions can be stabilized using fine particles such as colloids as a method other than emulsification using surfactants. Emulsions stabilized by the adsorption of fine particles to a liquid-liquid interface such as oil-water are called "fine particle-stabilized emulsions" or "Pickering emulsions." In recent years, research into fine particle-stabilized emulsions (Pickering emulsions) has been actively conducted (e.g., Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2019 / 087666 [Patent Document 2] International Publication No. 2019 / 240239 Summary of the Invention [Problem to be solved by the invention]

[0008] However, conventional Pickering emulsions have room for improvement in terms of emulsion stability. There is also a need for Pickering emulsions that use novel materials to address dairy allergies and be environmentally friendly.

[0009] The first objective of the present invention is to provide an emulsion composition that uses ingredients appropriate for addressing milk allergies and is environmentally friendly, and that also has excellent emulsion stability (including long-term storage stability).The second objective is to provide an animal-derived food substitute that does not contain animal-derived ingredients, thereby contributing to reducing the environmental impact, which is a social issue. [Means for solving the problem]

[0010] As a result of extensive research aimed at solving the above problems, the inventors of the present invention have come up with the idea of ​​using insect proteins as solid particles adsorbed at the liquid-liquid interface of Pickering emulsions. The use of insect proteins is believed to contribute to addressing milk allergies and being environmentally friendly. However, it was found that amphiphilic substances contained as impurities in commercially available insect protein raw materials may impair the emulsion stability of Pickering emulsions. Therefore, in the present invention, the insect protein obtained after reducing the content of amphiphilic substances in commercially available insect protein raw materials is used as the solid particles in Pickering emulsions, thereby improving the emulsion stability of Pickering emulsions.

[0011] The present invention has the following aspects. [1] Contains water, oil, and solid particles; the solid particles are present at the interface between the water and the oil, at least a portion of the solid particles are insect proteins; An oil-in-water emulsion composition, wherein the pH of the aqueous phase or the aqueous dispersion containing the solid particles is 7.5 or less. [2] The oil-in-water emulsion composition according to [1], wherein the surface tension of the aqueous phase is 32 mN / m or more. [3] The oil-in-water emulsion composition according to [1] or [2], wherein at least a portion of the solid particles is at least one protein selected from the group consisting of silkworm protein, cricket protein, and grasshopper protein. [4] Contains water, oil, and solid particles; the solid particles are present at the interface between the water and the oil, at least a portion of the solid particles are insect proteins; An oil-in-water emulsion composition, wherein the surface tension of the aqueous phase is 32 mN / m or more. [5] The oil-in-water emulsion composition according to [4], wherein the pH of the aqueous phase or the aqueous dispersion containing the solid particles is 7.5 or less. [6] The oil-in-water emulsion composition according to [4] or [5], wherein at least a portion of the solid particles are at least one protein selected from the group consisting of silkworm protein, cricket protein, and grasshopper protein. [7] A method for producing an oil-in-water emulsion composition comprising water, oil, and solid particles, the solid particles being present at the interface between the water and the oil, comprising: The method of manufacturing the solid particles comprises using an insect protein obtained after removing at least a portion of the amphiphilic substance from an insect protein raw material. [8] The production method described in [7], further comprising adjusting the pH of the protein aqueous dispersion obtained by stirring the insect protein and the water to 7.5 or less, and then stirring the protein aqueous dispersion and the solid particles. [9] The production method according to [7] or [8], wherein at least a portion of the solid particles is at least one protein selected from the group consisting of silkworm protein, cricket protein, and grasshopper protein.

[10] A food product comprising the oil-in-water emulsion composition according to any one of [1] to [6].

[11] A milk substitute comprising the oil-in-water emulsion composition according to any one of [1] to [6].

[12] A pharmaceutical product comprising the oil-in-water emulsion composition according to any one of [1] to [6].

[13] A cosmetic product comprising the oil-in-water emulsion composition according to any one of [1] to [6].

[14] A personal care product comprising the oil-in-water emulsion composition according to any one of [1] to [6]. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide an emulsion composition that uses raw materials that are suitable from the viewpoints of addressing milk allergies and being environmentally friendly, and that also has excellent emulsion stability. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is an SEM image of silkworm powder used in the examples (photograph in place of drawing). [Figure 2]This is an SEM image of the cricket powder used in the examples (photograph in place of a drawing). [Figure 3] This is an SEM image of the grasshopper powder used in the examples (photograph in place of a drawing). [Figure 4] 1 shows the results of zeta potential measurement and hydrodynamic diameter measurement at each pH of the silkworm powder used in the examples (photographs in place of drawings). [Figure 5] These are the results of zeta potential measurements and hydrodynamic diameter measurements at each pH of the cricket powder used in the examples (photographs in place of drawings). [Figure 6] These are the results of zeta potential measurements and hydrodynamic diameter measurements of the grasshopper powder used in the examples at each pH (photos in place of drawings). [Figure 7] 1 shows the zeta potential measurement results and hydrodynamic diameter of castor oil water dispersions at each pH. [Figure 8] 1 is an optical microscope photograph (drawing substitute photograph) of oil-in-water emulsion composition D1 prepared in Comparative Example 8. [Figure 9] 1 is an optical microscope photograph (drawing substitute photograph) of oil-in-water emulsion composition D2 prepared in Comparative Example 8. [Figure 10] 1 is an optical microscope photograph (drawing substitute photograph) of oil-in-water emulsion composition D3 prepared in Comparative Example 8. [Figure 11] 1 shows the results of zeta potential measurement and hydrodynamic diameter measurement at each pH of the silkworm particle aqueous dispersion B1 prepared in Preparation Example (photographs in place of drawings). [Figure 12] 1 is an optical microscope photograph (a photograph substituting a drawing) of a silkworm particle aqueous dispersion A1 prepared in Preparation Example. [Figure 13] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm particle aqueous dispersion A2 prepared in Preparation Example. [Figure 14] 1 is an optical microscope photograph (photograph substitute for drawing) of the silkworm particle aqueous dispersion A4 prepared in Preparation Example. [Figure 15] 1 is an SEM image (photograph in place of a drawing) of the dried powder of the silkworm particle water dispersion C4-1 (before washing) prepared in Preparation Example. [Figure 16]1 is an optical microscope photograph (photograph substituting a drawing) of a silkworm particle aqueous dispersion C1 (before washing) prepared in a preparation example. [Figure 17] 1 is an optical microscope photograph (photograph substituting a drawing) of a silkworm particle aqueous dispersion C4 (before washing) prepared in a preparation example. [Figure 18] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition A2 prepared in the example. [Figure 19] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition A3 prepared in the example. [Figure 20] 1 is an optical microscope photograph (a photograph substituting a drawing) of a silkworm emulsion composition A1 prepared in a comparative example. [Figure 21] 1 is an optical microscope photograph (photograph substituting a drawing) of silkworm emulsion composition A4 prepared in a comparative example. [Figure 22] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition B1 prepared in the example. [Figure 23] 1 is an optical microscope photograph (photograph substituting a drawing) of the silkworm emulsion composition B2 prepared in the example. [Figure 24] 1 is an optical microscope photograph (a photograph substituting a drawing) of silkworm emulsion composition B3 prepared in a comparative example. [Figure 25] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition C1 prepared in the example. [Figure 26] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition C2 prepared in the example. [Figure 27] 1 is an optical microscope photograph (photograph substituting a drawing) of a silkworm emulsion composition C3 prepared in a comparative example. [Figure 28] 1 is an optical microscope photograph (a photograph substituting a drawing) of a silkworm emulsion composition B1-1 prepared in a comparative example. [Figure 29] 1 is an optical microscope photograph (a photograph substituting a drawing) of a silkworm emulsion composition B1-10 prepared in a comparative example. [Figure 30] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition C4 prepared in the example. [Figure 31]1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition C5 prepared in the example. [Figure 32] 1 is an optical microscope photograph (a photograph substituting a drawing) of a silkworm emulsion composition C6 prepared in a comparative example. [Figure 33] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition C9 prepared in the example. [Figure 34] 1 is an optical microscope photograph (a photograph substituting a drawing) of the silkworm emulsion composition C10 prepared in the example. [Figure 35] This shows the results of zeta potential measurement and hydrodynamic diameter measurement at each pH of the cricket particle aqueous dispersion C0 prepared in the preparation example (photographs in place of drawings). [Figure 36] This is an optical microscope photograph of cricket particle water dispersion A1 prepared in Preparation Example (photograph substitute for drawing). [Figure 37] This is an optical microscope photograph of cricket particle water dispersion A2 prepared in Preparation Example (photograph substitute for drawing). [Figure 38] This is an optical microscope photograph of cricket particle water dispersion A3 prepared in Preparation Example (photograph substitute for drawing). [Figure 39] 1 is an optical microscope photograph of cricket emulsion composition A1 prepared in the example (photograph substitute for drawing). [Figure 40] 1 is an optical microscope photograph of cricket emulsion composition A2 prepared in the example (photograph substitute for drawing). [Figure 41] 1 is an optical microscope photograph of cricket emulsion composition A3 prepared in a comparative example (photograph substitute for drawing). [Figure 42] 1 is an optical microscope photograph of cricket emulsion composition C1 prepared in the example (photograph substitute for drawing). [Figure 43] 1 is an optical microscope photograph of cricket emulsion composition C2 prepared in a comparative example (photograph substitute for drawing). [Figure 44] These are the results of zeta potential measurements and hydrodynamic diameter measurements at each pH of the grasshopper particle aqueous dispersion C0 prepared in the preparation example (photographs in place of drawings). [Figure 45] This is an optical microscope photograph of grasshopper particle water dispersion A1 prepared in Preparation Example (photograph substitute for drawing). [Figure 46] This is an optical microscope photograph of grasshopper particle water dispersion A2 prepared in Preparation Example (photograph substitute for drawing). [Figure 47] This is an optical microscope photograph of grasshopper particle water dispersion A3 prepared in Preparation Example (photograph substitute for drawing). [Figure 48] 1 is an optical microscope photograph of the grasshopper emulsion composition A1 prepared in the example (photograph substitute for drawing). [Figure 49] 1 is an optical microscope photograph of the grasshopper emulsion composition A2 prepared in the example (photograph substitute for drawing). [Figure 50] 1 is an optical microscope photograph of grasshopper emulsion composition A3 prepared in a comparative example (photograph substitute for drawing). [Figure 51] 1 is an optical microscope photograph of the grasshopper emulsion composition C1 prepared in the example (photograph substitute for drawing). [Figure 52] 1 is an optical microscope photograph of the grasshopper emulsion composition C2 prepared in the comparative example (photograph substitute for drawing). DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail. The following description of the components relates to one example, a representative example, or a preferred example of the embodiment of the present invention, and the present invention is not limited to these examples.

[0015] [Oil-in-water emulsion composition] One embodiment of the present invention relates to an oil-in-water emulsion composition. The oil-in-water emulsion composition contains water, oil, and solid particles. In the oil-in-water emulsion composition, the solid particles are present at the interface between the water and the oil. In the oil-in-water emulsion composition, at least a portion of the solid particles are insect proteins. In one embodiment, the pH of the aqueous phase or the aqueous dispersion containing the solid particles is 7.5 or less. In another embodiment, the surface tension of the aqueous phase is 32 mN / m or more.

[0016] In this specification, the term "oil-in-water emulsion composition" refers to a so-called O / W type oil-in-water emulsion composition in which the continuous phase is water, as well as multiphase emulsions such as a W / O / W type oil-in-water emulsion composition.

[0017] As used herein, "solid particles" refers to particles that are insoluble or poorly soluble in a medium that can be used in an oil-in-water emulsion composition, such as water and oils and fats (poorly soluble is preferred, and insoluble is more preferred). In this context, "insoluble" or "poorly soluble" refers to particles that are dispersible without dissolving in a solvent (medium). In other words, particles whose particle diameter (major axis size, etc.) in a solvent (medium) can be specified.

[0018] From the viewpoint of maintaining the emulsion structure and emulsion stability of the present invention, it is preferable that the solid particles do not melt during the process of producing / processing the oil-in-water emulsion composition. From this viewpoint, the melting point of the solid particles under atmospheric pressure is usually 20°C or higher, preferably 65°C or higher, more preferably 80°C or higher, even more preferably 100°C or higher, particularly preferably 120°C or higher, especially preferably 150°C or higher, and most preferably 160°C or higher. By using solid particles with a melting point within this range, it is possible to obtain an oil-in-water emulsion composition having high heat resistance.

[0019] The emulsion composition according to the present embodiment is emulsified by solid particles. In this case, "emulsified" can be rephrased as a state in which the solid particles are present at the interface between water and oil constituting the oil-in-water emulsion composition. In addition, in the emulsion composition, the solid particles are usually present at the interface between water and oil, but are not limited thereto, and may include solid particles dispersed in water or oil.

[0020] (solid particles) In one embodiment, the solid particles are particles that are insoluble in a medium that can be applied to the oil-in-water emulsion composition, such as water and oils and fats, and therefore do not dissolve in the aqueous phase component and the oil phase component used in the oil-in-water emulsion composition, and the aqueous phase and / or the oil phase can be stirred even after the solid particles are added to the aqueous phase component and / or the oil phase component. The solid particles may be one type of solid particles or a combination of two or more types of solid particles selected arbitrarily. The solid particles before being dispersed in a medium may be in the form of a powder, a paste, or pellets.

[0021] In one embodiment, at least a portion of the solid particles is insect protein (hereinafter, solid particles containing insect protein may be referred to as insect-derived particles or insect particles. For example, they may be referred to as silkworm-derived particles, silkworm particles, cricket-derived particles, cricket particles, grasshopper-derived particles, or grasshopper particles). The insect protein is prepared from an insect protein raw material. For example, commercially available insect protein raw materials contain impurities, at least a portion of which are amphiphilic substances. Examples of insect protein raw materials include insect pulverization (insect powder), its crudely purified products, and classified products.

[0022] The insect protein is not particularly limited, but examples thereof include silkworm protein, cricket protein, and grasshopper protein. Of these, silkworm protein and cricket protein are preferred, and silkworm protein is more preferred.

[0023] By appropriately selecting and using insect proteins, it is possible to provide foods that do not contain dairy-derived substances, which is a countermeasure against dairy allergies, as well as wheat- and gluten-free foods, which are a countermeasure against celiac disease and wheat allergies caused by the intake of wheat flour.

[0024] In one embodiment of the present invention, emulsion stability is enhanced by washing the insect protein raw material until the surface tension of the aqueous phase is 32 mN / m or more, because it is believed that the higher the surface tension of the aqueous phase, the more likely it is that the content of amphiphilic substances such as surfactants can be reduced. In the case of silkworm proteins, the surface tension of the aqueous phase is preferably 32 mN / m or more, more preferably 35 mN / m or more, and even more preferably 40 mN / m or more. In the case of cricket proteins, the surface tension of the aqueous phase is preferably 32 mN / m or more, more preferably 35 mN / m or more, and even more preferably 40 mN / m or more. In the case of grasshopper protein, the surface tension of the aqueous phase is preferably 32 mN / m or more, more preferably 35 mN / m or more, and even more preferably 40 mN / m or more.

[0025] The amphipathic substance is not particularly limited, but for example, a water-soluble amphipathic substance (glycolipid, fatty acid, phospholipid, water-soluble protein, etc.) is preferred. Examples of the water-soluble amphipathic substance include water-soluble surfactants. Examples of water-soluble surfactants include nonionic surfactants (nonionic surfactants) and ionic surfactants (anionic surfactants, cationic surfactants, amphoteric surfactants), with ionic surfactants being preferred as the water-soluble surfactant. Examples of nonionic surfactants include monoglycerides, diglycerides, neutral glycolipids, etc. Examples of ionic surfactants include ionic lipids such as phospholipids, ionic glycolipids (acidic glycolipids), and fatty acids, water-soluble proteins, and free amino acids.

[0026] Examples of phospholipids include lysolecithin, phosphatidylcholine, phosphatidylinositol, phosphatidylserine, lysophosphatidylcholine, phosphatidylethanolamine, N-acylphosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidylglycerol, and phosphatidic acid.

[0027] A portion of the solid particles may be one type of insect protein, or two or more types of insect proteins may be used in combination. Furthermore, a portion of the solid particles may contain components other than insect proteins. The insect protein content in the solid particles is usually 5% by mass or more, preferably 10% by mass or more, more preferably 30% by mass or more, even more preferably 50% by mass or more, even more preferably 80% by mass or more, particularly preferably 90% by mass or more, especially preferably 95% by mass or more, and most preferably 100% by mass.

[0028] Examples of components other than insect proteins include water, lipids, minerals, dietary fiber, etc. These may be adsorbed to or encapsulated in part of the insect proteins. By removing a portion of the amphiphilic substance contained as an impurity from the insect protein raw material so that the physical properties or composition ratio fall within the above ranges, the amphiphilic substance can be adsorbed first to the oil-water interface, thereby preventing physical interference with the interfacial adsorption of solid particles, thereby imparting a high degree of emulsion stability to the emulsion composition.

[0029] When the amphiphilic substance contained in the insect protein raw material is, in particular, an ionic amphiphilic substance or a low-molecular-weight amphiphilic substance, the ionic amphiphilic substance or the low-molecular-weight amphiphilic substance will be present before the solid particles adsorb to the oil-water interface to be stabilized, and for example, the oil droplet surface will temporarily become highly negatively charged in absolute terms, which will undesirably inhibit the adsorption of the negatively charged solid particles due to electrostatic repulsion or physical obstruction, thereby inhibiting the adsorption of the solid particles to the interface.In other words, by emulsifying the plant protein from which a portion of the ionic amphiphilic substance has been removed, an emulsion composition with excellent emulsion stability can be obtained.

[0030] Other proteins may be used in combination with the insect protein. The other proteins are preferably hydrophobic proteins. A hydrophobic protein refers to a protein that contains a large amount of hydrophobic amino acids among its constituent amino acids. The inclusion of a large amount of hydrophobic amino acids reduces the water solubility of the protein, forming a hydrophobic protein. Examples of hydrophobic amino acids include leucine, isoleucine, valine, phenylalanine, proline, glutamine, and asparagine. Examples of hydrophobic proteins include proteins derived from grasses (rice protein, etc.).

[0031] Solid particles containing insect proteins can also be evaluated by measuring the contact angle with water. The contact angle is usually 0° or more, preferably 5° or more, more preferably 10° or more, even more preferably 15° or more, particularly preferably 20° or more, especially preferably 40° or more, most preferably 50° or more, and especially preferably 65° or more. There is no upper limit to the contact angle, but from the perspective of handling during production, such as dispersion in an aqueous phase and cleaning of containers / equipment, the contact angle is usually less than 180°, preferably 150° or less, more preferably 130° or less, even more preferably 110° or less, particularly preferably 90° or less, and most preferably 80° or less.

[0032] The contact angle can be measured at room temperature using a contact angle measuring device, by forming solid particles into a tablet, dropping water onto the tablet under its own weight, and measuring the contact angle over time after dropping water. To minimize the influence of surface irregularities and liquid absorption into the porous parts of the tablet, the contact angle at the time of droplet landing (t=0) is calculated by linear approximation using the measured value at which the change in contact angle with time (t) after droplet landing is approximately linear. This can be used as the contact angle of water on the solid particles.

[0033] When the contact angle of water with solid particles containing insect proteins falls within the above range, the wettability of the solid particles becomes moderately hydrophobic. When such a substance having moderate hydrophobicity is used for the solid particles, it is possible to efficiently emulsify water with oils and fats (animal oils, vegetable oils, edible oils, etc.) that are less polar than hydrocarbons such as n-dodecane, and form an emulsion structure in which the solid particles are adsorbed to the oil-water interface, thereby obtaining an emulsion composition with good emulsion stability.

[0034] In one embodiment, the solid particles are composed of insect protein. In another embodiment, the content of the insect protein relative to the total mass of the solid particles is typically 1 to 100% by mass, preferably 3 to 100% by mass, more preferably 5 to 100% by mass, even more preferably 10 to 100% by mass, particularly preferably 50 to 100% by mass, especially preferably 60 to 100% by mass, most preferably 70 to 100% by mass, or even 100% by mass. In yet another embodiment, the content of at least one protein selected from glutelin and prolamin relative to the total mass of the solid particles may be 0.1 to 100% by mass, preferably 1 to 100% by mass, more preferably 3 to 100% by mass, even more preferably 5 to 100% by mass, especially preferably 10 to 100% by mass, especially preferably 20 to 100% by mass, and most preferably 50 to 100% by mass.

[0035] In one embodiment, the protein constituting the solid particles may be subjected to physical treatment such as UV irradiation, heat, or pressure, or chemical treatment such as acid, alkali, denaturant (e.g., urea, guanidine hydrochloride, organic solvents such as alcohol, surfactants), enzyme, oxidizing agent, reducing agent, or chelating agent. Such treatments can physically and / or chemically modify (denaturate, etc.) the protein, thereby controlling the wettability of the protein or particles formed from the protein (protein aggregates, protein-containing complexes). That is, proteins with appropriate wettability are more likely to be present at the interface to be stabilized (the interface between the oil phase and the aqueous phase), allowing the formation of a stable oil-in-water emulsion composition. Furthermore, treatments such as heating, pressurization, or UV irradiation can also be expected to have a sterilizing effect that prevents spoilage of the material itself.

[0036] The treatment may be performed alone, or two or more arbitrarily selected treatments may be performed simultaneously or separately. For example, a denaturant is added to a medium containing a protein, and heat is applied. This allows denaturation treatment with a denaturant and denaturation treatment with heat to be performed simultaneously. The denaturation method can be selected taking into consideration the type of protein to be denatured, the required degree of denaturation, and the like. For example, when heat treatment is performed, either dry heating or wet heating may be used. There are no limitations on the equipment used, but in the case of dry heating, for example, a roasting equipment, a hot air heating equipment, or a microwave heating equipment can be used. In the case of wet heating, a humidified heating equipment, a steaming equipment, or a steam heating equipment can be used. The heating temperature is usually 30°C or higher, preferably 40°C or higher, more preferably 50°C or higher, more preferably 60°C or higher, more preferably 70°C or higher, and even more preferably 80°C or higher. The upper limit of the heating temperature is a temperature at which the protein does not completely decompose or evaporate, i.e., below 200°C. The heat treatment time may be any time, and is usually 10 seconds or more, preferably 30 seconds or more, more preferably 1 minute or more, more preferably 5 minutes or more, more preferably 10 minutes or more, even more preferably 15 minutes or more, and particularly preferably 30 minutes or more.

[0037] The shape of the solid particles is not limited, and examples thereof include spherical, rod-like, string-like, mesh-like, porous, needle-like, and flake-like shapes. Here, the solid particles may be in the form of a gel containing a medium (water, oil, gas, etc.), and in the case of a gel, the solid particles may be shrunk or swollen. The solid particles may be formed from a single component, or may be formed from a mixture of a plurality of different components. The solid particles may or may not form aggregates or associations. When the solid particles form aggregates or associations, the solid particles may have an entanglement structure, or a crosslinked structure due to hydrogen bonds, ionic bonds, intermolecular forces, or the like.

[0038] The primary particle size of the solid particles is not particularly limited and may be appropriately selected depending on the particle size of the oil phase, the type of protein constituting the solid particles, etc. The primary particle size is usually 0.001 μm or more, preferably 0.01 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, and particularly preferably 0.5 μm or more, and is usually 5 cm or less, preferably 10 mm or less, more preferably 1 mm or less, particularly preferably 500 μm or less, and even more preferably 250 μm or less.

[0039] The primary particle diameter of the solid particles is, for example, an average particle diameter of particles observable on a magnified particle image obtained by scanning electron microscope (SEM) measurement. The number of particles observed may be 5 or more, 20 or more, 40 or more, 100 or more, or 200 or more. When commercially available solid particles are used, the primary particle diameter of the solid particles may be determined by referring to the catalog value.

[0040] The average particle size of the solid particles is not particularly limited as long as the effects of the present invention are achieved, and can be appropriately selected depending on the particle size of the oil phase, the type of protein constituting the solid particles, etc. The volume-based average particle size of the solid particles dilutedly dispersed in a liquid is usually 0.01 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, even more preferably 0.5 μm or more, particularly preferably 1 μm or more, especially preferably 5 μm or more, and most preferably 10 μm or more, and is usually 200 μm or less, preferably 150 μm or less, more preferably 80 μm or less, even more preferably 60 μm or less, particularly preferably 50 μm or less, especially preferably 40 μm or less, most preferably 30 μm or less, and especially preferably 20 μm or less.

[0041] The lower limit and upper limit of the volume-based average particle size can be combined arbitrarily, and in one embodiment, it is 0.01 μm or more and 100 μm or less, 0.05 μm or more and 80 μm or less, 0.1 μm or more and 60 μm or less, 1 μm or more and 50 μm or less, or 3 μm or more and 50 μm or less, in another embodiment, it is 5 μm or more and 30 μm or less, and in still another embodiment, it is 10 μm or more and 20 μm or less.

[0042] Here, the term "dilute state" refers to any concentration, but refers to a concentration that can be measured using a laser diffraction / scattering particle size distribution analyzer, such as a flow type. The concentration to be measured is usually 20% by mass or less, preferably 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0.02% by mass or less, relative to the total mass of the sample to be measured.

[0043] The volume-based median diameter of the solid particles dispersed in a dilute state in a liquid is usually 0.01 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, even more preferably 0.5 μm or more, particularly preferably 1 μm or more, especially preferably 5 μm or more, and most preferably 10 μm or more, and usually 100 μm or less, preferably 80 μm or less, more preferably 60 μm or less, even more preferably 50 μm or less, especially preferably 40 μm or less, especially preferably 30 μm or less, and most preferably 20 μm or less.

[0044] The lower and upper limits of the volume-based median diameter can be combined arbitrarily, and in one embodiment, it is 0.01 μm or more and 100 μm or less, 0.05 μm or more and 80 μm or less, 0.1 μm or more and 60 μm or less, 1 μm or more and 50 μm or less, or 3 μm or more and 50 μm or less, in another embodiment, it is 5 μm or more and 30 μm or less, and in still another embodiment, it is 10 μm or more and 20 μm or less. By setting the size of the solid particles in the medium within the above range, the dispersibility of the solid particles in the medium is improved, the probability of contact with the oil-water interface is improved, and the solid particles can be efficiently adsorbed to the oil-water interface.Furthermore, the solid particles adsorbed to the oil-water interface can be prevented from detaching from the interface and settling due to the influence of gravity, so that a stable emulsion composition can be obtained.

[0045] The size of solid particles can be measured, for example, by using a laser diffraction / scattering particle size distribution analyzer to measure the particle size distribution, average particle size, or median size of solid particles in a powder or dispersed state in a liquid. The analysis conditions may be either number-based or volume-based, but volume-based analysis is more preferable. When it is difficult to perform measurements using a laser diffraction / scattering particle size distribution analyzer, the particle size distribution, average particle size, or median size of solid particles dispersed in a liquid may be measured using dynamic light scattering. Measurement results using dynamic light scattering can be analyzed, for example, using the cumulant method. When measurements can be performed using either a laser diffraction / scattering particle size distribution analyzer or dynamic light scattering, it is preferable to perform the measurements using a laser diffraction / scattering particle size distribution analyzer.

[0046] In one embodiment, from the viewpoint of dispersion of the solid particles constituting the oil-in-water emulsion composition, particle size control, etc., it is preferable to separately subject the solid particles to crushing, pulverizing, or dispersion treatment. There are no limitations on the method of these treatments, and the treatment may be carried out in a dry system or a wet system. Crushing and / or crushing, or dispersion treatment may be carried out in stages using a combination thereof.

[0047] Wet processing methods include ultra-high pressure homogenizers, high-pressure homogenizers, homogenizers, jet mills, vibration mills, tumbling mills, high-pressure fluid impact mills, paint shakers, bead mills, ball mills, disk mills, and homomixers (homomixers). Dry processing methods include pin mills, jet mills, ball mills, hammer mills, roller mills, cutter mills, impact shear mills, and crushing / disintegration treatments using an agate mortar. Ultra-high pressure homogenizers, high-pressure homogenizers, bead mills, cutter mills, and hammer mills are preferred. Ultra-high pressure homogenizers and high-pressure homogenizers are particularly preferred, with ultra-high pressure homogenizers being more preferred. Use of a high-pressure homogenizer or ultra-high pressure homogenizer can better prevent undesirable contamination of inorganic substances derived from the beads.

[0048] When beads are used in wet processing, beads with a diameter of about 0.05 to 5 mm are preferably used. There are no restrictions on the material of the beads, but glass beads, special glass beads, alumina beads, zirconia-silica ceramic beads, zirconia beads, silicon nitride beads, steel beads, etc. can be used.

[0049] The temperature during treatment is usually −196° C. or higher, preferably −80° C. or higher, more preferably −40° C. or higher, even more preferably −20° C. or higher, particularly preferably 0° C. or higher, especially preferably 4° C. or higher, and most preferably 20° C. or higher. The temperature during treatment is usually 100° C. or lower, preferably 90° C. or lower, more preferably 80° C. or lower, even more preferably 75° C. or lower, especially preferably 70° C. or lower, especially preferably 65° C. or lower, and most preferably 60° C. or lower.

[0050] The treatment time is usually 30 seconds or more, preferably 1 minute or more, more preferably 1 minute 30 seconds or more, more preferably 2 minutes or more, even more preferably 30 minutes or more, particularly preferably 1 hour or more, and most preferably 2 hours or more. The treatment time can usually be 10 hours or less, preferably 8 hours or less, more preferably 7 hours or less, and even more preferably 6 hours or less. If the treatment time is too short, particle size control tends to be difficult, and if the treatment time is too long, productivity tends to decrease.

[0051] In one embodiment, in order to produce solid particles that are components of an oil-in-water emulsion composition, the disintegrated particles obtained by the above-described production method may be subjected to a particle size classification treatment. The classification conditions may be such that the mesh size is usually 150 μm or less, preferably 106 μm or less, more preferably 53 μm or less, more preferably 45 μm or less, more preferably 38 μm or less, and even more preferably 20 μm or less.

[0052] There are no particular restrictions on the equipment used for the classification process, but for example, in the case of dry sieving, a rotary sieve, a shaking sieve, a swirling sieve, or a vibrating sieve can be used; in the case of dry airflow classification, a gravity classifier, an inertia classifier, or a centrifugal classifier (classifier, cyclone, etc.) can be used; and in the case of wet sieving, a mechanical wet classifier, a hydraulic classifier, a sedimentation classifier, or a centrifugal wet classifier can be used.

[0053] In one embodiment, the size of the solid particles present at the interface between the aqueous phase and the oil phase in the oil-in-water emulsion composition is not particularly limited as long as the effects of the present invention are achieved. The number-based average particle size of the solid particles is usually 0.01 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, even more preferably 0.2 μm or more, particularly preferably 0.5 μm or more, especially preferably 0.7 μm or more, and most preferably 1 μm or more, and can be usually 50 μm or less, preferably 30 μm or less, more preferably 20 μm or less, even more preferably 10 μm or less, particularly preferably 8 μm or less, especially preferably 6 μm or less, and most preferably 3 μm or less.

[0054] The lower limit and upper limit of the average particle size can be combined arbitrarily, and in one embodiment, it is 0.05 μm or more and 30 μm or less, and 0.1 μm or more and 20 μm or less, in another embodiment, it is 0.5 μm or more and 15 μm or less, and in still another embodiment, it is 1 μm or more and 10 μm or less.

[0055] The solid particles (insect proteins) present at the interface between water and oil may be present in a state where they maintain their size and shape in the dispersion medium, or may be present in a layered or aggregated state at the interface. The solid particles (vegetable proteins) may be densely adsorbed at the interface between water and oil, or may be layered due to intermolecular interactions, i.e., present in a film-like state. In the case of a film state, the film pressure is defined as the above size. If the size of the solid particles present at the water phase-oil phase interface is within the above range, they will not feel strange in the mouth and will not impair the texture.

[0056] The number-based average particle size of solid particles present at the aqueous-oil phase interface is, for example, the average particle size of particles observed on a magnified particle image obtained by measurement using an optical microscope or a scanning electron microscope (SEM). Observation using a scanning electron microscope is preferred. The number of particles observed may be 5 or more, 40 or more, 100 or more, or 200 or more.

[0057] When it is difficult to measure using a laser diffraction / scattering particle size distribution analyzer, the particle size distribution, average particle size, or median size of solid particles dispersed in a liquid may be measured by dynamic light scattering. The results of measurements using dynamic light scattering can be analyzed, for example, by the cumulant method.

[0058] In one embodiment, the content of solid particles in the oil-in-water emulsion composition is not particularly limited, as long as it is an amount that can normally be contained in an oil-in-water emulsion composition, but is usually 0.001% by mass or more, preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, particularly preferably 0.5% by mass or more, especially preferably 1% by mass or more, and most preferably 2% by mass or more, relative to the total mass of the oil-in-water emulsion composition, and is usually 50% by mass or less, preferably 40% by mass or less, more preferably 30% by mass or less, particularly preferably 20% by mass or less, especially preferably 10% by mass or less, and most preferably 5% by mass or less.

[0059] The lower limit and upper limit of the solid particle content can be arbitrarily combined, and in one embodiment, the solid particle content can be 0.01% by mass or more and 30% by mass or less, 0.05% by mass or more and 20% by mass or less, or 0.1% by mass or more and 10% by mass or less, relative to the total mass of the oil-in-water emulsion composition, and in another embodiment, 0.5% by mass or more and 5% by mass or less. If the content of solid particles is equal to or less than the upper limit, thickening of the emulsion when dispersed in a medium is suppressed, and handling tends to be easy. If the content of solid particles is equal to or more than the lower limit, adsorption of the solid particles to the interface between water and oil when forming an emulsion composition, i.e., coating of oil droplets with the solid particles, tends to be sufficient, and sufficient emulsion stabilization function (stabilization due to adsorption to the interface between water and oil) that can withstand long-term storage tends to be imparted.

[0060] (oil phase component) In one embodiment, the oil contained in the oil-in-water emulsion composition forms an oil phase, and therefore may be referred to as an oil phase component in this specification. The oil phase component is not particularly limited as long as it is one that can be used in an oil-in-water emulsion composition, and examples of such oil phase components include unsaturated higher fatty acid hydrocarbons, unsaturated higher fatty acids, animal and vegetable oils and fats, isoprenoids including squalene and tocopherol, higher alcohols, synthetic ester oils, glycol higher fatty acid esters, saturated fatty acids, and unsaturated fatty acids.

[0061] The oil phase component preferably contains any of those usable for food (hereinafter referred to as "edible oils"), cosmetics, and pharmaceuticals, and any of these oil phase components can be used. Among these, the use of animal and vegetable oils (hereinafter referred to as "oils") is preferred, and from an environmental perspective, the use of vegetable oils, their hardened oils, and processed oils is even more preferred. Incidentally, physiologically functional oils, fat-soluble pigments, and antioxidants can also be used as the edible oils. Examples of the oils and fats include vegetable oils such as castor oil, rapeseed oil, rice oil, soybean oil, corn oil, safflower oil, sunflower oil, cottonseed oil, sesame oil, olive oil, palm oil, palm kernel oil, coconut oil, linseed oil, macadamia seed oil, camellia seed oil, tea seed oil, rice bran oil, and cocoa butter; animal oils and fats such as milk fat, beef tallow, lard, chicken fat, mutton tallow, and fish oil; and oils and fats obtained by processing liquid or solid vegetable oils or animal oils such as these, such as refining, deodorizing, fractionating, hardening, or interesterification. For example, hardened oils and processed oils such as hardened coconut oil and hardened palm kernel oil; and liquid oils or solid fats obtained by fractionating these oils and fats. One or more of the following may be used. In addition, physiologically functional fats and oils can also be used, and specific examples thereof include docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), arachidonic acid, α-linolenic acid, γ-linolenic acid, medium-chain triglycerides (MCT), etc. These fats and oils may be used alone or in combination.

[0062] The edible oils and fats may also include fat-soluble pigments and antioxidants, such as carotenoid pigments (e.g., annatto pigment, β-carotene, paprika pigment, carrot carotene, and dinaliella carotene), monascus pigment, chlorophyll, turmeric pigments (e.g., curcumin (curcuminoid)), and edible tar-based pigments. Examples of antioxidants include plant extracts such as rosemary extract, tea extract, green coffee bean extract, grape seed extract, and bayberry extract, tocopherol, tocotrienol, ascorbyl palmitate, dibutylhydroxytoluene, and butylhydroxyanisole.

[0063] The iodine value of the oil or fat is generally 200 or less, preferably 150 or less, more preferably 130 or less, even more preferably 100 or less, particularly preferably 95.0 or less, and most preferably 90.0 or less. By setting the iodine value within such a preferred range, the degree of unsaturation of the fatty acids constituting the oil or fat becomes low, which makes the oil or fat relatively resistant to oxidation, and deterioration of the oil or fat, such as oxidized odor, can be suppressed.

[0064] Furthermore, it is preferable that the melting point of the oil or fat is generally -100°C or higher, preferably -80°C or higher, more preferably -60°C or higher, even more preferably -40°C or higher, particularly preferably -30°C or higher, and most preferably -20°C or higher. The upper limit of this melting point is preferably 70°C or lower, more preferably 50°C or lower, even more preferably 20°C or lower, particularly preferably 10°C or lower, and most preferably 0°C or lower. By setting the melting point within this preferred range, good emulsion stability can be obtained. The melting point can be measured by a known method using a DSC, a melting point measuring device, or the like.

[0065] In one embodiment, the oil constituting the oil phase of the oil-in-water emulsion composition forms oil droplets. In this specification, the oil droplets may be simply referred to as the oil phase, and the term "average particle size of the oil phase" refers to the average particle size of the oil droplets. Furthermore, the term "median diameter of the oil phase" refers to the median diameter of the oil droplets.

[0066] In another embodiment, the average particle size of the oil phase is preferably 2.2 μm or more. The average particle size of the oil phase refers to the size of the discontinuous phase of the oil-in-water emulsion composition, i.e., the average diameter of the oil phase in an O / W emulsion or a W / O / W emulsion. By setting the average particle size of the oil phase to the above value, it is possible to improve the texture, appearance, tactile feel, viscosity, stability, etc. The average particle size of the oil phase is usually greater than 0.5 μm, preferably 1 μm or more, more preferably 2.2 μm or more, even more preferably 3 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more. Although there is no upper limit, the average particle size of the oil phase is usually 5 cm or less, preferably 10 mm or less, more preferably 1 mm or less, even more preferably 500 μm or less, particularly preferably 400 μm or less, especially preferably 300 μm or less, and most preferably 250 μm or less.

[0067] The lower limit and upper limit of the average particle size can be combined arbitrarily, and in one embodiment, it is 0.5 μm or more and 1 mm or less, in another embodiment, it is 1 μm or more and 500 μm or less, and in still another embodiment, it is 1 μm or more and 300 μm or less. Here, the preferred range of the median diameter of the oil phase is the same as the preferred range of the average particle diameter of the oil phase described above.

[0068] Such an emulsion structure can be confirmed by observation with a polarizing microscope. The size of the discontinuous phase, i.e., the oil phase, is the average size of the major axis of the discontinuous phase confirmed by observation with a polarizing microscope. The discontinuous phase confirmed may be 10 or more, 20 or more, 40 or more, 50 or more, 100 or more, or 200 or more.

[0069] Alternatively, the size of the discontinuous phase of the oil-in-water emulsion composition, i.e., the particle size distribution, median size, or average particle size of the oil phase in the O / W emulsion, can be measured using a laser diffraction / scattering particle size distribution analyzer or a measuring device using dynamic light scattering. When measuring using a laser diffraction / scattering particle size distribution analyzer, there are no limitations on the analysis conditions, but it is preferable to analyze on a volume basis.

[0070] In one embodiment, the content of the oil phase component, i.e., fat or oil, in the oil-in-water emulsion composition is not particularly limited as long as it is an amount that allows the formation of an oil-in-water emulsion composition, but is usually 0.01% by mass or more, preferably 0.1% by mass or more, more preferably 1% by mass or more, even more preferably 5% by mass or more, particularly preferably 10% by mass or more, especially preferably 15% by mass or more, and most preferably 20% by mass or more, relative to the total mass of the oil-in-water emulsion composition. Furthermore, the content of the oil or fat, relative to the total mass of the oil-in-water emulsion composition, is usually less than 80% by mass, preferably 70% by mass or less, more preferably 60% by mass or less, even more preferably 50% by mass or less, particularly preferably 40% by mass or less, especially preferably 30% by mass or less, and most preferably 25% by mass or less.

[0071] The lower limit and upper limit of the content of the oil phase component, i.e., the oil or fat, in the oil-in-water emulsion composition can be combined in any desired manner. In one embodiment, the content is from 0.01% by mass to 30% by mass, both inclusive, relative to the total mass of the oil-in-water emulsion composition. In another embodiment, the content is from 0.1% by mass to 25% by mass, both inclusive, relative to the total mass of the oil-in-water emulsion composition. In yet another embodiment, the content is from 1% by mass to 25% by mass, both inclusive, relative to the total mass of the oil-in-water emulsion composition.

[0072] In the oil-in-water emulsion composition of this embodiment, it is preferable that the change in diameter of the oil phase, which is the discontinuous phase of the emulsion composition, is small before and after heating, such as sterilization. The change in diameter before and after freezing or heating is calculated by taking the median diameter (D50) of the oil-in-water emulsion composition before freezing or heating as 100% and calculating the percentage difference from the median diameter (D50) of the oil-in-water emulsion composition after freezing or heating. The median diameter (D50) after heating may be ±100% or less, ±90% or less, ±80% or less, ±75% or less, ±50% or less, ±30% or less, ±20% or less, or ±10% or less.

[0073] (Aqueous phase component) In one embodiment, the water contained in the oil-in-water emulsion composition forms an aqueous phase, which is a continuous phase in the oil-in-water emulsion composition. The components forming the aqueous phase may be any components that are typically incorporated into the oil-in-water emulsion composition to form the aqueous phase. The aqueous phase components include at least water, and may also include a lower alcohol, a polyhydric alcohol, or the like.

[0074] In one embodiment, the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is preferably 7.5 or less. In an aqueous dispersion of insect protein, the lower the pH, the closer the zeta potential of the insect protein particle surface tends to be to the isoelectric point. The closer the zeta potential of the insect protein particle surface is to the isoelectric point, the less repulsion with negatively charged oil droplets there is. This promotes adsorption of solid particles to the oil-water interface, further improving emulsion stability. The upper limit of the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is usually 13 or less, preferably 7.5 or less, more preferably 7.0 or less, even more preferably 6.5 or less, particularly preferably 6.0 or less, especially preferably less than 5, and most preferably 4.9 or less. The lower limit of the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is usually greater than 1, preferably 3.5 or more, more preferably 3.6 or more, even more preferably 3.7 or more, especially preferably 3.8 or more, especially preferably 3.9 or more, and most preferably 3.0 or more.

[0075] The upper and lower limits of the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles can be arbitrarily combined. In the case of silkworm proteins, the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is preferably 3.5 to 7.5, more preferably 3.7 to 7.5, even more preferably 3.7 to 7.0, and particularly preferably 3.7 to 4.9. In the case of cricket protein, the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is preferably 3.3 to 7.5, more preferably 3.5 to 7.5, even more preferably 3.7 to 7.0, and particularly preferably 3.7 to 4.9. In the case of locust protein, the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is preferably 3.3 to 7.5, more preferably 3.5 to 7.5, even more preferably 3.7 to 7.0, and particularly preferably 3.7 to 4.9. When the pH of the aqueous phase or the pH of the aqueous dispersion containing solid particles is within the above range, repulsion between the solid particles and the negatively charged oil droplets is suppressed, which promotes adsorption of the solid particles to the oil-water interface and further improves emulsion stability. The pH of the oil-in-water emulsion composition itself may be in the same preferred pH range as the aqueous phase, but may also be adjusted to the pH described below depending on the intended use of the oil-in-water emulsion composition.

[0076] In one embodiment, the water content in the oil-in-water emulsion composition is not particularly limited as long as it is an amount that can form an oil-in-water emulsion composition, but is usually 20% by mass or more, preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, particularly preferably 60% by mass or more, especially preferably 70% by mass or more, and most preferably 75% by mass or more, based on the total mass of the oil-in-water emulsion composition. Furthermore, the water content is usually less than 100% by mass, preferably 99% by mass or less, more preferably 98% by mass or less, even more preferably 97% by mass or less, particularly preferably 95% by mass or less, especially preferably 90% by mass or less, and most preferably 80% by mass or less, based on the total mass of the oil-in-water emulsion composition.

[0077] The lower limit and upper limit of the water content in the oil-in-water emulsion composition can be combined in any manner, and in one embodiment, the water content is 40% by mass or more and less than 100% by mass, relative to the total mass of the oil-in-water emulsion composition; in another embodiment, the water content is 50% by mass or more and 99% by mass or less, relative to the total mass of the oil-in-water emulsion composition; in yet another embodiment, the water content is 60% by mass or more and 98% by mass or less, relative to the total mass of the oil-in-water emulsion composition; and in yet another embodiment, the water content is 70% by mass or more and 95% by mass or less, relative to the total mass of the oil-in-water emulsion composition.

[0078] (Other ingredients) In one embodiment, the oil-in-water emulsion composition may further contain a colorant, an antioxidant, a sweetener, a stabilizer, a milk component, a flavoring, a colorant, a salt, an organic acid, or the like, within a range that does not impair the effects of the present invention.

[0079] Sweeteners include the following: Sugars: monosaccharides such as glucose, fructose, wood sugar, sorbose, galactose, or isomerized sugar; disaccharides such as sucrose, maltose, lactose, isomerized lactose, or palatinose; oligosaccharides such as fructooligosaccharides, maltooligosaccharides, isomaltooligosaccharides, galactooligosaccharides, coupling sugar, or palatinose; Sugar alcohols: monosaccharide alcohols such as erythritol, sorbitol, xylitol, or mannitol; disaccharide alcohols such as maltitol, isomaltitol, or lactitol; trisaccharide alcohols such as maltotriitol, isomaltotriitol, or panitol; tetrasaccharide or higher alcohols such as oligosaccharide alcohols; powdered reduced maltose starch syrup, etc. High-intensity sweeteners: such as aspartame, neotame, sucralose, or stevia.

[0080] Stabilizers include galactomannan, xanthan gum, carrageenan, gum arabic, tamarind gum, gellan gum, glucomannan, cellulose, and the like.

[0081] Examples of dairy components include liquids such as milk, processed milk, skim milk, fresh cream, whey, buttermilk, sweetened condensed milk, and evaporated milk; and powdered dairy products such as whole milk powder, skim milk powder, modified milk powder, powdered cream, powdered whey, and buttermilk powder. Buttermilk or buttermilk powder is particularly preferred. Buttermilk is a liquid component called buttermilk or butterserum, which is separated when the milk fat portion is extracted as butter by churning or other methods from cream produced from milk by centrifugation or other methods. This liquid is concentrated to form concentrated buttermilk, and powdered buttermilk powder is further spray-dried. These may be used alone or in combination of two or more. Separately, during the process of separating cream or butter from milk, fermentation by acid-producing bacteria or the addition of an acid such as an organic acid may be performed. However, the buttermilk that can be used in the present invention is preferably buttermilk that has not undergone such fermentation or acid addition. As the buttermilk, commercially available products such as "Buttermilk Powder" manufactured by Yotsuba Dairy Products Co., Ltd. can be used.

[0082] As mentioned above, from the viewpoint of ensuring that the oil-in-water emulsion composition does not contain any allergens, it is preferable that the milk component does not contain casein or β-lactoglobulin, which are highly allergenic, and it is more preferable that the milk component does not contain any milk-derived proteins. Furthermore, it is preferable to use casein or β-lactoglobulin after hydrolyzing it with an enzyme or acid to a molecular weight that is sufficiently low so as not to exhibit allergenicity. The content of milk-derived components in the emulsion composition is usually 0.5% by mass or less, preferably 0.2% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, even more preferably 0.01% by mass or less, and particularly preferably 0.005% by mass or less, and it is particularly preferred that the emulsion composition is substantially free of milk-derived components. "Substantially free of milk-derived components" means that the emulsion composition of this embodiment does not contain any milk-derived components other than impurities contained in purified products prepared from animal, plant, or fungal raw materials. The above range is preferred from the viewpoint of allergies.

[0083] Any flavoring agent can be used. Examples include vanilla flavorings such as vanilla essence; milk flavors such as milk flavors or butter flavors; and the like, with milk flavors being particularly preferred. The milk flavoring is not particularly limited as long as it is a flavoring containing the aroma components of milk and contains the aroma components characteristic of milk. It may be a chemically synthesized flavoring, a flavoring extracted and purified from milk, or a mixture thereof, but those made from milk are more preferred, and milk flavorings produced by reacting milk components with enzymes are even more preferred because they can reproduce the natural flavor of milk. These may be used alone or in combination of two or more types.

[0084] Any coloring agent can be used, including, for example, cocoa color, β-carotene, annatto color, chili pepper color, turmeric color, oil red color, paprika color, naphthol yellow color, and riboflavin butyrate (VB2).

[0085] Examples of salts include chlorides such as table salt, potassium chloride, and magnesium chloride; carbonates such as sodium carbonate, potassium carbonate, and calcium carbonate; bicarbonates such as sodium bicarbonate and potassium bicarbonate; phosphates such as disodium phosphate, trisodium phosphate, dipotassium phosphate, and tripotassium phosphate; sodium polyphosphate; citrates such as sodium citrate; and sodium lactate. Magnesium-containing salts are particularly preferred, and examples of salts that can be used in food applications include whey minerals, magnesium chloride, magnesium oxide, magnesium carbonate, magnesium sulfate, bittern (crude seawater magnesium chloride), dolomite, crude salt, magnesium stearate, magnesium monohydrogen phosphate, trimagnesium phosphate, magnesium silicate, magnesium hydroxide, magnesium acetate, magnesium citrate, magnesium malate, magnesium benzoate, magnesium gluconate, magnesium L-glutamate, sepiolite, talc, and phytin.

[0086] Examples of organic acids include fumaric acid, succinic acid, citric acid, tartaric acid, diacetyltartaric acid, malic acid, adipic acid, glutaric acid, and maleic acid.

[0087] (Action and effect) The oil-in-water emulsion composition of the present invention has an emulsion structure in which solid particles are present at the interface between the oil phase component and the aqueous phase component. Such a structure allows the emulsion composition to have excellent emulsion stability. The structure in which solid particles are present at the interface between the oil phase component and the aqueous phase component refers to a structure in which solid particles are adsorbed to the interface between the oil phase component and the aqueous phase component. This makes it possible, for example, to emulsify the oil phase in the aqueous phase, forming a so-called Pickering emulsion. Specifically, this refers to a structure in which at least a portion of the solid particles are adsorbed to the surface of the oil phase emulsified in the aqueous phase. In the oil-in-water emulsion composition described above, the pH of the aqueous phase or the aqueous dispersion containing solid particles is 7.5 or less, which is believed to result in the zeta potential of the surface of the insect protein-containing solid particles being close to the isoelectric point. This suppresses repulsion between the insect protein-containing solid particles and the negatively charged oil droplets. As a result, adsorption of the solid particles to the oil-water interface is promoted, further improving emulsion stability. In another embodiment, the surface tension of the aqueous phase is 32 mN / m or more, which is believed to reduce the content of amphiphilic substances such as surfactants. Because amphiphilic substances can impair the emulsion stability of a Pickering emulsion, a surface tension of 32 mN / m or more ensures good adsorption of solid particles to the surface of the oil phase emulsified in the aqueous phase, allowing the above-described structure to be efficiently formed (good coverage of the oil droplets by the solid particles). Having such a structure is believed to improve the emulsion stability of the Pickering emulsion. The presence of solid particles at the interface between the oil and aqueous phase components can be confirmed not only by observation with an optical microscope, but also by using a cryo-scanning electron microscope (Cryo-SEM) or other device to rapidly freeze an oil-in-water Pickering emulsion using a rapid freezing method such as the metal contact method, then cutting the frozen Pickering emulsion in a cryomicrotome with a diamond knife for an optical microscope to prepare a sample, and then observing the cross section of the sample with a Cryo-SEM.

[0088] [Method of producing oil-in-water emulsion composition] In one embodiment, the method for producing an oil-in-water emulsion composition includes using an insect protein obtained after removing at least a portion of the amphiphilic substance from an insect protein raw material as the solid particles. Commercially available insect protein raw materials contain impurities, at least a portion of which are amphiphilic substances. In one embodiment, emulsion stability is enhanced by washing the insect protein raw material to reduce the content of amphiphilic substances. It is believed that using the insect protein obtained after washing the insect protein raw material to form solid particles in an oil-in-water emulsion composition promotes adsorption of the solid particles to the oil-water interface, thereby improving emulsion stability. The specific method for washing the insect protein raw material (a step of removing at least a portion of the impurities in the insect protein raw material) is not particularly limited. The method may be washing with water, washing with an organic solvent, washing with an ion exchange resin, a method using gel filtration chromatography, or a method using an ultrafiltration membrane. Examples of organic solvents include, but are not limited to, hexane, chloroform, alcohols, and the like. In addition to water, aqueous solutions such as buffer solutions containing salts, and mixtures thereof, may also be used for washing. Among these, washing with water or an aqueous solution is preferred. Compared to degreasing with an organic solvent such as n-hexane, washing without using an organic solvent (washing with water, washing with an ion exchange resin or an ultrafiltration membrane, etc.) is advantageous in that the prepared composition does not contain organic solvents that may have adverse effects on the human body, and therefore is expected to be highly safe when used in food applications. In addition, it is also safe in that no flammable substances are used in the manufacturing process. Furthermore, washing without using an organic solvent is advantageous from the perspective of reducing environmental impact.

[0089] The oil-in-water emulsion composition can be produced by a method known per se, except that the solid particles are insect proteins obtained after washing an insect protein raw material. For example, the oil-in-water emulsion composition can be produced by mixing the solid particles, an oil phase component, an aqueous phase component, and optionally other components, and stirring the resulting mixture using any stirring device.

[0090] Although there are no particular limitations, specifically, it can be obtained by preparing it by the following method. A production method comprising: step A1 of mixing an aqueous phase component with an insect protein to form a mixture and stirring the mixture; and step A2 of mixing the mixture obtained in step A1 with the oil phase component to form a mixture and stirring the mixture. Alternatively, a production method including a step A1' of mixing the oil phase component and the insect protein to form a mixture and stirring the mixture, and a step A2' of mixing the mixture obtained in the above step with an aqueous phase component to form a mixture and stirring the mixture.

[0091] Step A1 is a step of preparing an aqueous phase. Adding insect protein to an aqueous phase to prepare an insect protein dispersion facilitates the formation of an oil-in-water emulsion composition. The pH of the insect protein aqueous dispersion is preferably 7.5 or less. It is believed that maintaining the pH of the insect protein aqueous dispersion at 7.5 or less allows the zeta potential of the insect protein surface to approach the isoelectric point. This reduces the repulsion between solid particles containing insect protein and negatively charged oil droplets. This promotes adsorption of the solid particles to the oil-water interface, further improving emulsion stability.

[0092] The upper limit of the pH of the aqueous dispersion of insect protein is usually 13 or less, preferably 7.5 or less, more preferably 7.0 or less, even more preferably 6.5 or less, particularly preferably 6.0 or less, especially preferably less than 5, and most preferably 4.9 or less. The lower limit of the pH of the aqueous dispersion of insect protein is usually greater than 1, preferably 3.5 or more, more preferably 3.6 or more, even more preferably 3.7 or more, especially preferably 3.8 or more, especially preferably 3.9 or more, and most preferably 3.0 or more.

[0093] The upper and lower limits of the pH of the aqueous dispersion of the insect protein can be arbitrarily combined. In the case of silkworm protein, the pH of the aqueous dispersion is preferably 3.5 to 7.5, more preferably 3.7 to 7.5, even more preferably 3.7 to 7.0, particularly preferably 3.9 to 6.8, especially preferably 4.0 to 6.5, and most preferably 3.7 to 4.9. In the case of cricket protein, the pH of the aqueous dispersion is preferably 3.5 to 7.5, more preferably 3.7 to 7.5, even more preferably 3.7 to 7.0, particularly preferably 3.9 to 6.8, especially preferably 4.0 to 6.5, and most preferably 3.7 to 4.9. In the case of grasshopper protein, the pH of the aqueous dispersion is preferably 3.5 to 7.5, more preferably 3.7 to 7.5, even more preferably 3.7 to 7.0, particularly preferably 3.9 to 6.8, especially preferably 4.0 to 6.5, and most preferably 3.7 to 4.9. When the pH of the aqueous dispersion is within the above range, repulsion between the negatively charged oil droplets and the solid particles is suppressed, which promotes adsorption of the solid particles to the oil-water interface and further improves emulsion stability.

[0094] Here, the insect protein can be obtained by washing the insect protein raw material to reduce at least a portion of the amphiphilic substance. In one embodiment, an aqueous dispersion of a commercially available insect protein raw material is prepared by stirring or the like, and then the aqueous dispersion of the insect protein raw material is washed with water (including gravity settling, centrifugation, filtration with a filter, or suction filtration) or with an ion exchange resin to prepare an aqueous phase. Before washing, the insect protein raw material may be finely divided in advance by processing it in an agate mortar, or by performing a crushing / disintegration process such as freeze-pulverization or dry-pulverization, or classification, and the aqueous phase may be prepared using this finely divided protein raw material. The prepared aqueous phase can be treated with a wet-type atomization device (e.g., a homogenizer, a high-pressure homogenizer, an ultra-high-pressure homogenizer, an ultrasonic homogenizer, a bead mill, a ball mill, etc.) to atomize (also called micronization) and disperse the solid particles in the aqueous phase.

[0095] Step A1' is a step of preparing an oil phase. After the insect protein is present in the oil phase, a water phase may be added.

[0096] The mixture in steps A1 and A1' may be stirred at room temperature and pressure, or at elevated temperature and / or elevated pressure. There are no limitations on the stirring speed or stirring time, but a speed of 10 rpm or more and 20,000 rpm or less is usually sufficient, and the stirring time is usually 10 seconds or more and 5 hours or less. The stirring speed or stirring time may be changed stepwise.

[0097] Examples of stirring devices include high-pressure emulsifiers, paddle mixers, homogenizers, ultrasonic homogenizers, colloid mills, kneaders, in-line mixers, static mixers, onlaters, and homomixers. Homomixers (homomixers), paddle mixers, and homogenizers are preferred because they can perform sufficient stirring with low energy and low cost. Homomixers are more preferred because they have a wide convection range and can stir the entire mixture uniformly. Different stirring devices may also be used in combination.

[0098] Steps A2 and A2' are steps for preparing an oil-in-water emulsion composition. The mixture in step A2 is typically stirred at elevated temperatures to fully melt the oily component, usually at 10°C to 100°C, preferably 20°C to 90°C, more preferably 30°C to 90°C, even more preferably 40°C to 90°C, particularly preferably 50°C to 90°C, and most preferably 60°C to 90°C. The stirring speed is usually 10 rpm to 20,000 rpm, and the stirring time is usually 10 seconds to 60 minutes.

[0099] Although there are no limitations on the stirring conditions, by gradually changing the stirring speed and stirring time, it is possible to form a more stable oil-in-water emulsion composition. Specifically, by finely dispersing oil droplets by high-speed stirring in the first stage and then stirring at a slower speed in the second stage than in the first stage, adsorption of solid particles to the oil-water interface is promoted, resulting in emulsion stabilization. Furthermore, during the second stage of stirring, poor adsorption of solid particles to the oil-water interface due to shear forces generated by the equipment during high-speed stirring in the first stage is suppressed, and detachment of solid particles once adsorbed to the interface from the interface is also suppressed.

[0100] When the stirring conditions are changed stepwise, the stirring speed in the first stage is usually 3000 rpm or more, more preferably 5000 rpm or more, more preferably 7000 rpm or more, and even more preferably 8000 rpm or more. There is no upper limit to the stirring speed, but it is usually 25000 rpm or less, preferably 20000 rpm or less, more preferably 18000 rpm or less, more preferably 16000 rpm or less, even more preferably 14000 rpm or less, particularly preferably 12000 rpm or less, and most preferably 10000 rpm or less. The stirring time in the first stage is usually 30 seconds or more, preferably 1 minute or more. There is no upper limit to the stirring time, but it is usually 1 hour or less, preferably 30 minutes or less, more preferably 15 minutes or less, and especially preferably 5 minutes or less.

[0101] When the stirring conditions are changed stepwise, the stirring speed in the second stage may typically be 10 rpm or higher, preferably 100 rpm or higher, 500 rpm or higher, 1000 rpm or higher, 2000 rpm or higher, or 2500 rpm or higher. There is no upper speed limit, but the stirring speed in the second stage may typically be 10,000 rpm or lower, preferably 8,000 rpm or lower, 6,000 rpm or lower, or 3,000 rpm or lower. There is no particular limit to the stirring time, but from the viewpoint of promoting adsorption of the solid particles to the oil-water interface, it is typically 30 seconds or longer, preferably 1 minute or longer, more preferably 10 minutes or longer, and even more preferably 20 minutes or longer.

[0102] After preparing the oil-in-water emulsion composition, it is usually 60 ° C or higher, preferably 65 ° C or higher, more preferably 75 ° C or higher, even more preferably 80 ° C or higher, particularly preferably more than 95 ° C, especially preferably 100 ° C or higher, most preferably 110 ° C or higher, and usually 160 ° C or lower, preferably 150 ° C or lower, usually for 0.01 minutes or more, preferably 0.03 minutes or more, and usually for 60 minutes or less, preferably 30 minutes or less. The sterilization method is not particularly limited, but examples include UHT sterilization, retort sterilization, and Joule sterilization. UHT sterilization can be performed by a direct heating method such as a steam injection method in which steam is blown directly into the composition or a steam infusion method in which the composition is heated by injecting steam into the composition; an indirect heating method using a surface heat exchanger such as a plate or tube, and can be performed by a method known per se, for example, a plate-type sterilizer can be used.

[0103] [Uses of oil-in-water emulsion composition] The oil-in-water emulsion composition can be used for pharmaceuticals, cosmetics, foods, feeds, diagnostic agents, carriers for drug delivery systems (DDS), detergents, coating agents, surface treatment agents, toiletries, and personal care products, for example, for oral ingestion or transdermal absorption, and can also be used as a production intermediate thereof.

[0104] That is, the oil-in-water emulsion composition of the present invention may be an oil-in-water emulsion composition for food, an oil-in-water emulsion composition for cosmetic use, or an oil-in-water emulsion composition for pharmaceutical use, may be a food-grade, cosmetic-grade, or pharmaceutical-grade oil-in-water emulsion composition, or may be a food, cosmetic, or pharmaceutical product containing the oil-in-water emulsion composition. The oil-in-water emulsion composition itself may be provided as a food, cosmetic, or pharmaceutical product (a pharmaceutical product containing an active pharmaceutical ingredient).

[0105] In one embodiment, any of the oil-in-water emulsion composition, food-grade oil-in-water emulsion composition, and food-grade oil-in-water emulsion composition can be used in the production of food products. By appropriately combining these compositions with other food production raw materials and / or food production preparations (intermediates), and mixing and / or processing (including high-temperature treatment such as sterilization), desired foods can be produced, making it possible to provide foods containing the oil-in-water emulsion composition. By including the oil-in-water emulsion composition of the present invention, it is possible to achieve a quality taste with a suitable texture and flavor, as well as long-term storage stability. Specific examples of foods are described below.

[0106] In another embodiment, any of the oil-in-water emulsion compositions, cosmetic-grade oil-in-water emulsion compositions, and cosmetic-grade oil-in-water emulsion compositions can be used in the production of cosmetics. By appropriately combining and mixing and / or processing these compositions with other raw materials for the production of cosmetics and / or preparations for the production of cosmetics (including intermediates and / or active ingredients for cosmetics), desired cosmetics can be produced, making it possible to provide cosmetics containing the oil-in-water emulsion composition. By including the oil-in-water emulsion composition of the present invention, cosmetics with excellent usability, such as a favorable texture and ease of application, can be produced.

[0107] In another embodiment, any of the oil-in-water emulsion compositions, pharmaceutical-grade oil-in-water emulsion compositions, and pharmaceutical-grade oil-in-water emulsion compositions can be used in the production of pharmaceuticals. These compositions can be appropriately combined with other raw materials for pharmaceutical production and / or pharmaceutical preparations for pharmaceutical production (intermediates and / or active pharmaceutical ingredients, etc.) and mixed and / or processed (including high-temperature treatments such as sterilization) to produce desired pharmaceuticals, making it possible to provide pharmaceuticals containing the oil-in-water emulsion composition. By including the oil-in-water emulsion composition of the present invention, pharmaceuticals with excellent usability and favorable texture, feel, and flavor (including masking of bitterness) can be obtained.

[0108] When used for oral ingestion, there are no restrictions on the product, use, properties, etc., as long as it is taken orally. Specific uses include: beverages, liquid foods, cream foods, milk substitutes and other animal-derived food substitutes; retort nutritional supplements; functional foods such as liquid diets; oral vaccines; processed wheat flour products such as bread and noodles; processed oils and fats such as fat spreads and flower paste; various sauces and soups such as curry, coffee creamer, mayonnaise, dressings, mousse, pasta sauce, stew, demi-glace sauce, white sauce, or tomato sauce; retort foods and compound seasonings such as Chinese food mixes and rice bowl mixes; yogurts, These include sweets and desserts such as cheese, ice cream, cream, caramel, candy, chewing gum, chocolate, cookies and biscuits, cakes, pies, snacks, crackers, Japanese sweets, rice snacks, bean snacks, jelly, and pudding; processed livestock products such as hamburgers, meatballs, and canned seasoned meat; frozen foods; refrigerated foods; cooked and semi-cooked foods such as packaged and over-the-counter prepared foods; ready-to-eat foods such as instant noodles, cup noodles, instant soups and stews; fortified foods; foods and beverages such as liquid diets, high-calorie foods, and infant nutritional products; and tube feeding preparations.

[0109] In particular, beverages and liquid foods are preferred. Examples of beverages include milk beverages, soup beverages, coffee beverages, cocoa beverages, tea beverages (black tea, green tea, Chinese tea, etc.), bean / grain beverages, and acidic beverages. Among these, milk beverages, coffee beverages, and tea beverages are preferred. Animal-derived food substitutes refer to emulsified compositions that can replace animal-derived milks such as cow's milk in terms of taste, flavor, and physical properties. Examples of animal-derived food substitutes include milk substitutes, dairy-like foods and beverages that do not contain animal-derived dairy products, and condensed milk. Milk substitutes are also called plant-based milks. Examples of plant-based milks include almond beverages, oat beverages, coconut beverages, rice milk, cashew milk, hemp milk, pea milk, walnut beverages, soy milk, pistachio milk, barley milk, macadamia milk, and fruit juice beverages.

[0110] The emulsion composition according to one embodiment can also be used as an intermediate in the production of foods such as yogurt and ice cream. Examples of the physical properties include the particle size distribution of oil droplets in the composition, viscosity, pH, emulsion stability, and appearance. Furthermore, the food-grade oil-in-water emulsion composition and / or food-grade oil-in-water emulsion composition of the present invention, which is one embodiment, can be suitably used in packaged beverages such as canned drinks, PET bottled drinks, paper-packaged drinks, and bottled drinks. Another example of an animal-derived food substitute is meat substitute. Meat substitute refers to a food product made from raw materials other than meat, without containing animal-derived products or ingredients such as dairy products. Meat substitutes are also known as meat substitutes, meat substitutes, mock meat, artificial meat, and imitation meat.

[0111] The pH of products containing an oil-in-water emulsion composition (foods, cosmetics, pharmaceuticals, or intermediates for producing them) may be adjusted to a suitable range depending on the intended use and product. For example, when applied to foods, the pH may be edible or drinkable, with the lower limit typically being greater than pH 1, preferably pH 3 or higher, more preferably pH 4 or higher, even more preferably pH 5 or higher, particularly preferably pH 5.5 or higher, especially preferably pH 6 or higher, and most preferably pH 6.5 or higher. The upper limit typically being pH 13 or lower, preferably pH 10 or lower, more preferably pH 9.5 or lower, even more preferably pH 9.0 or lower, especially preferably pH 8.5 or lower, especially preferably pH 8.0 or lower, and most preferably pH 7.5 or lower. By setting the content in the above preferred range, it is possible to maintain better emulsion stability. By setting the content in the above range, it is possible to maintain a suitable size of the dispersed phase (oil droplet diameter), thereby making it possible to maintain a good texture when eaten.

[0112] The insect proteins and oils disclosed in this specification are known per se and can be produced or obtained by producing them according to known methods or by purchasing commercially available products. [Example]

[0113] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following description.

[0114] [Measurement method] The measurement method is as follows. (Particle size of solid particles or oil phase (oil droplets) which is the internal phase of emulsion) The diameter of the solid particles or oil droplets, which are the internal phase of the emulsion composition, was measured as the volume-average particle diameter (Dv) using a laser diffraction / scattering particle size distribution analyzer (MASTER SIZER 2000, Malvern). Measurements were performed five times using distilled water as the dispersion medium and a dispersion unit (Hydro2000SM, Malvern) at a stirring speed of 2000 rpm. The average of the five measurements was taken as the volume-average particle diameter (Dv) of the silkworm particles in a wet state (in aqueous medium).

[0115] (pH) The pH was measured using a pH meter (CyberDcan pH110, EUTECH).

[0116] (Microscopic observation) Measurement objects such as solid particles and emulsions were observed using either a scanning electron microscope (SEM, Keyence, VE-8800) or an optical microscope (Motic BA200, Shimadzu Rika Kikai Co., Ltd.) equipped with a digital camera (Moticam2000, Shimadzu Rika Co., Ltd.).

[0117] (Zeta potential measurement) Zeta potential measurements of each sample (silkworm-derived particles, cricket-derived particles, and grasshopper-derived particles) and castor oil at each pH level were performed using a zeta potential measurement device (Zetasizer Nano ZS, Malvern) equipped with an automatic titrator (MPT-2, Malvern). Specifically, the sample was adjusted to pH 10 by adding aqueous sodium hydroxide (98%, Sigma-Aldrich), and then gradually increased by adding hydrochloric acid (0.5 mol / L, Sigma-Aldrich) from the initial pH level. Using the same device, the hydrodynamic diameter of the sample was measured at each pH level by dynamic light scattering at a scattering angle of 173°.

[0118] A sample for measuring the zeta potential of castor oil was prepared as follows: First, 10 ml of an isopropanol solution of castor oil (1 wt% castor oil; hereafter, isopropanol will be abbreviated as IPA) was added to 100 g of water while stirring at 400 rpm using a magnetic stirrer (MAGNETIC STIRRER RS-1DN, AS ONE Corporation). Stirring was continued for one week, and the IPA was removed by evaporation, yielding a castor oil-water dispersion. Furthermore, when measuring the aqueous dispersions of each insect powder (silkworm powder, cricket powder, and grasshopper powder) described below, the particle diameter was too large to use particles collected from a homogeneous system, making measurement difficult. Therefore, the particles were redispersed and allowed to stand overnight, and the fine particles present in the supernatant were used for measurement.

[0119] (Measurement of surface and interfacial tension) An automatic surface tensiometer (DY-300, AUTOMATIC SURFACE TENSIOMER, Kyowa Interface Science Co., Ltd.) was used. Surface tension was measured by the Wilhelmy method. The interfacial tension was measured using the ring method. The measurements were carried out at room temperature of 21 to 25°C.

[0120] (Moisture measurement) The moisture content was quantified by Karl Fischer coulometry (thermal evaporation-coulometric titration) under the following conditions using a moisture measuring device ("CA-200" manufactured by Nitto Seiko Analytech Co., Ltd.) and a moisture vaporizer ("VA-200" manufactured by Nitto Seiko Analytech Co., Ltd.). The conditions for measuring the moisture content are as follows. ·Moisture measurement method: heating vaporization-coulometric titration method Moisture evaporation temperature: 150℃ Nitrogen gas flow rate: 300 mL / min Anolyte: Aquamicron AKX (Mitsubishi Chemical Corporation) Catholyte: Aquamicron CXU (Mitsubishi Chemical Corporation) Titration start delay time: 5 minutes End point detection level: 0.1μg / s

[0121] (organic elemental analysis) Using an organic elemental analyzer (UNICUBE, manufactured by Elemental), CHNS analysis was carried out under the conditions of a combustion tube temperature of 1150°C and a reduction tube temperature of 850°C. A combustion improver (tungsten oxide) was added to the sample at a ratio of 1:4.

[0122] (amino acid analysis) Samples for free amino acid analysis were prepared as follows. 10 mg of sample was weighed. 1 ml of ultrapure water was added to the 10 mg sample, and then ultrasonic waves were applied. 300 μL of the water-soluble fraction was subjected to ultrafiltration (MWCO: 10,000). The membrane-permeate fraction was used as a sample for free amino acid analysis.

[0123] Samples for hydrolysis amino acid analysis were prepared as follows. Five mg of sample was dispensed into a test tube. Hydrolysis was carried out for 1 hour at 150°C under a 6N hydrochloric acid atmosphere. After cooling, the hydrochloric acid was removed using a centrifugal evaporator, and the residue was redissolved in 200 μL of ultrapure water and centrifuged. 100 μL of the water-soluble fraction was then diluted 10-fold with 900 μL of ultrapure water. The mixture was then filtered through a 0.45 μm filter. The resulting filtrate was used as a sample for hydrolysis amino acid analysis.

[0124] Free amino acid analysis and hydrolyzed amino acid analysis were performed using the following equipment and under the following measurement conditions. The free amino acid analysis value was then subtracted from the hydrolyzed amino acid analysis value to calculate the BSA-equivalent protein content and free amino acid content.

[0125] Equipment: Hitachi Amino Acid Analyzer L-8900 Measurement conditions: Biological amino acid separation conditions - ninhydrin colorimetric method Standard: PF (Wako Amino Acid Mixture AN Type 0.8ml + B Type 0.8ml → 10ml) Asparagine, glutamine, tryptophan aqueous solution Injection volume: 10μL Quantitative calculation: Calculated from peak area using a single calibration curve

[0126] (Determination of emulsion type of emulsion) The emulsion type (O / W type or W / O type) of the emulsion was determined by visual observation of the appearance. Specifically, when the fluidity of the emulsion was high, it was determined to be an O / W type in which low-viscosity water was the continuous phase. When the fluidity of the castor oil emulsion was low, it was determined to be a W / O type in which high-viscosity castor oil was the continuous phase. Furthermore, in a composition in which the volume ratio of the water phase was higher than that of the oil phase, taking into account the addition ratio, when spherical or ellipsoidal structures, rather than lamellar, were clearly observed in the transparent liquid, it was also determined to be an O / W type.

[0127] When it was difficult to distinguish the emulsion type from appearance, a drop test was performed. In the drop test, if a few drops of the emulsion were dropped into water and dispersed, or if a few drops of the emulsion were dropped into castor oil and did not disperse well (if the emulsion floated on the surface of the castor oil or settled in the castor oil), it was determined that the continuous phase was water.

[0128] [Materials used] The raw materials used in the examples and their physical properties are as follows.

[0129] As the solid particles, any of the following was used. Silkworm powder (pupae) (TAKEO Co., Ltd., hereinafter referred to as silkworm powder) Black cricket powder (TAKEO Co., Ltd., hereafter referred to as cricket powder) Locust powder (TAKEO Co., Ltd., hereinafter referred to as locust powder)

[0130] SEM images of silkworm powder, cricket powder, and grasshopper powder are shown in Figures 1, 2, and 3, respectively. The zeta potential and hydrodynamic diameter of the measured particles are shown in Figures 4, 5, and 6, respectively.

[0131] Castor oil (Fujifilm Wako Pure Chemical Industries, Ltd.) was used as the oil phase component. The physical properties of castor oil, according to information from the reagent manufacturer, are as follows: Solubility: Insoluble in water, freely soluble in ethanol and acetone. Melting point / freezing point: -10 to -18°C Boiling point: 313℃ Density and / or relative density: 0.961 Saponification value: 175-190 Iodine value: 81-88

[0132] The results of measuring the zeta potential of the castor oil-water dispersions are shown in Figure 7. Although the details of the preparation will be described later, the O / W emulsion layers of emulsion composition D1, which is an emulsion of castor oil and water, emulsion composition D2, which is an emulsion of castor oil and an aqueous phase with a pH of 4, and emulsion composition D3, which is an emulsion of castor oil and an aqueous phase with a pH of 10, were sampled and observed under an optical microscope, and the results are shown in Figures 8, 9, and 10, respectively. These images are shown for reference as observation images of emulsions that do not contain solid particles in the composition.

[0133] Ion-exchanged water was used as the aqueous phase component. Ion-exchanged water (<0.06 mS / cm) was prepared using an ion-exchanged water production system (MFSRFD240NA:GA25A-0715, Advantec). The pH of the ion-exchanged water (hereinafter sometimes referred to as water) used was 6.5. The pH of the water and dispersion was adjusted using aqueous sodium hydroxide (98%, Sigma-Aldrich), aqueous citric acid (Fujifilm Wako Pure Chemical Industries, Ltd.), and aqueous hydrochloric acid (0.5 mol / L, Sigma-Aldrich). Table 1 shows the reference physical properties of each substance and those for comparison.

[0134] [Table 1]

[0135] [Preparation of aqueous dispersion of silkworm-derived particles] (Preparation Example 1) 96 parts by weight of ion-exchanged water and 4 parts by weight of silkworm powder were dispensed into a container so as to achieve the weight ratio shown in Table 2. These were stirred using a homogenizer at 12,000 rpm for 10 minutes to obtain a water dispersion A1 of silkworm-derived particles.

[0136] (Preparation Example 2) A water dispersion A2 of silkworm-derived particles was obtained in the same manner as in Preparation Example 1, except that silkworm powder, ion-exchanged water, and an aqueous citric acid solution were used in the weight ratios shown in Table 2 and at a pH of 4.

[0137] (Preparation Example 3) A water dispersion A3 of silkworm-derived particles was obtained in the same manner as in Preparation Example 1, except that silkworm powder, ion-exchanged water, and an aqueous hydrochloric acid solution were used in the weight ratios shown in Table 2 and at a pH of 4.

[0138] (Preparation Example 4) Silkworm-derived particle aqueous dispersion A4 was obtained in the same manner as in Preparation Example 1, except that silkworm powder, ion-exchanged water, and an aqueous sodium hydroxide solution were used in the weight ratios shown in Table 2 and at a pH of 10.

[0139] (Preparation Example 5) 96 parts by weight of ion-exchanged water and 4 parts by weight of silkworm powder were placed in a container and stirred at 12,000 rpm for 10 minutes using a homogenizer to obtain a water dispersion B1 of silkworm-derived particles (before washing).

[0140] Next, the silkworm particle aqueous dispersion B1 (before washing) was first centrifuged at 15,000 rpm for 10 minutes using a centrifuge (CF16RXII, HITACHI) under brake-free conditions, and the supernatant was removed.After that, the same amount of ion-exchanged water as the removed supernatant was added to the container containing the sediment and stirred.

[0141] Next, the container was centrifuged again, the supernatant was removed, and ion-exchanged water was added to the container and stirred. This centrifugal washing procedure was repeated a total of five times to obtain a silkworm-derived particle aqueous dispersion B1. The solids concentration, determined by measuring the dry weight of the silkworm-derived particle aqueous dispersion, was 2.2±0.09 wt %. This is shown in Table 2. The supernatants removed after the first, fifth, and tenth centrifugal washings are referred to as silkworm supernatant B1-1, silkworm supernatant B1-5, and silkworm supernatant B1-10, respectively.

[0142] (Preparation Example 6) Silkworm-derived particle aqueous dispersion B2 was obtained in the weight ratio shown in Table 2 in the same manner as in Preparation Example 5, except that after five centrifugation washing operations, demineralized water and citric acid solution were added to the container to adjust the pH to 4.

[0143] (Preparation Example 7) Silkworm-derived particle aqueous dispersion B3 was obtained in the weight ratio shown in Table 2 in the same manner as in Preparation Example 5, except that after five centrifugation washing operations, demineralized water and sodium hydroxide solution were added to the container to adjust the pH to 10.

[0144] (Preparation Example 8) The silkworm powder was crushed for 5 minutes in an agate mortar. Except for using this crushed silkworm powder, the same procedures as in Preparation Example 5 were repeated to obtain a silkworm-derived particle aqueous dispersion C1 (before washing), followed by a silkworm-derived particle aqueous dispersion C1. The solids concentration obtained by measuring the dry weight of the silkworm-derived particle aqueous dispersion C1 was 2.91±0.14% by weight. This is shown in Table 2.

[0145] (Preparation Example 9) Silkworm-derived particle aqueous dispersion C2 was obtained in the same manner as in Preparation Example 5, except that the crushed silkworm powder used was crushed in an agate mortar for 5 minutes, and that after five centrifugal washing operations, demineralized water and citric acid aqueous solution were added to the container to adjust the pH to 4 and the solid content to 2.91 weight ± 0.14%.

[0146] (Preparation Example 10) Silkworm-derived particle aqueous dispersion C3 was obtained in the same manner as in Preparation Example 5, except that the crushed silkworm powder used was crushed in an agate mortar for 5 minutes, and that after five centrifugal washing operations, demineralized water and aqueous sodium hydroxide solution were added to the container to adjust the pH to 10 and the solid content to 2.91 weight percent ± 0.14%.

[0147] (Preparation Example 11) 10 parts by weight of crushed silkworm powder, which had been crushed in an agate mortar for 5 minutes, and 80 parts by weight of ion-exchanged water were dispensed into a container. These were stirred using a homogenizer at 12,000 rpm for 10 minutes to obtain a silkworm particle aqueous dispersion C4. This was left to stand for 10 minutes to allow coarse particles to settle, and the supernatant was then dispensed to obtain a silkworm particle aqueous dispersion C4-1. Next, this silkworm particle aqueous dispersion C4-1 was centrifuged at 15,000 rpm for 10 minutes using a centrifuge (CF16RX II, HITACHI) under brake-free conditions. After removing the supernatant, the same amount of ion-exchanged water as the removed supernatant was added to the container containing the sediment and stirred. Next, this container was centrifuged again, and after removing the supernatant, ion-exchanged water was added to the container and stirred. This centrifugal washing procedure was repeated a total of five times to obtain silkworm-derived particle aqueous dispersion C4-2. The solids concentration obtained by measuring the dry weight of the silkworm-derived particle aqueous dispersion was 3.63 ± 0.04 wt %. This is shown in Table 2.

[0148] (Preparation Example 12) Silkworm particle aqueous dispersion C4-1 was centrifuged five times, and then demineralized water and citric acid solution were added to the container to adjust the pH to 4. The same procedure as in Preparation Example 11 was repeated to obtain silkworm particle aqueous dispersion C5-2 having the weight ratio shown in Table 2.

[0149] (Preparation Example 13) Silkworm particle aqueous dispersion C4-1 was centrifuged five times, and then demineralized water and sodium hydroxide solution were added to the container to adjust the pH to 10. Silkworm particle aqueous dispersion C6-2 was obtained in the weight ratio shown in Table 2 in the same manner as in Preparation Example 11.

[0150] (Preparation Example 14) 30 parts by weight of crushed silkworm powder, which had been crushed in an agate mortar for 5 minutes, and 70 parts by weight of ion-exchanged water were placed in a container. These were stirred at 12,000 rpm for 10 minutes using a homogenizer to obtain a silkworm-derived particle aqueous dispersion C7. This was left to stand for 10 minutes to allow coarse particles to settle, and the supernatant was then removed to obtain a silkworm particle aqueous dispersion C7-1. Next, this silkworm particle aqueous dispersion C7-1 was centrifuged at 15,000 rpm for 10 minutes using a centrifuge (CF16RX II, HITACHI) under brake-free conditions. After removing the supernatant, the same amount of ion-exchanged water as the removed supernatant was added to the container containing the sediment and stirred. Next, this container was centrifuged again, and after removing the supernatant, ion-exchanged water was added to the container and stirred. After repeating this centrifugal washing procedure a total of 35 times, a predetermined amount of ion-exchanged water and citric acid aqueous solution were added to achieve the weight ratio shown in Table 2, thereby obtaining silkworm-derived particle aqueous dispersion C7-2. The supernatants removed after the 1st, 15th, 25th, and 35th centrifugal washings are referred to as silkworm supernatant C7-2-1, silkworm supernatant C7-2-15, silkworm supernatant C7-2-25, and silkworm supernatant C7-2-30, respectively.

[0151] (Preparation Example 15) A water dispersion of silkworm particles C8-2 was obtained in the same manner as in Preparation Example 14, except that the content ratio of silkworm powder was adjusted to the ratio shown in Table 2.

[0152] (Preparation Example 16) A water dispersion of silkworm particles C9-2 was obtained in the same manner as in Preparation Example 14, except that the content ratio of silkworm powder was adjusted to the ratio shown in Table 2.

[0153] (Preparation Example 17) A water dispersion of silkworm particles C10-2 was obtained in the same manner as in Preparation Example 14, except that the content ratio of silkworm powder was adjusted to the ratio shown in Table 2.

[0154] [Table 2]

[0155] [Preparation of oil-in-water emulsion composition] Example 1 The silkworm-derived particle aqueous dispersion A2 and castor oil were dispensed into containers in the weight ratios shown in Table 3. These were stirred at 12,000 rpm at room temperature for 2 minutes using a homogenizer to obtain a silkworm oil-in-water emulsion composition A2.

[0156] Example 2 Silkworm oil-in-water emulsion composition A3 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion A3 was used.

[0157] Example 3 A silkworm oil-in-water emulsion composition B1 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion B1 was used.

[0158] Example 4 A silkworm oil-in-water emulsion composition B2 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion B2 was used.

[0159] Example 5 A silkworm oil-in-water emulsion composition C1 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C1 was used.

[0160] Example 6 A silkworm oil-in-water emulsion composition C2 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C2 was used.

[0161] Example 7 A silkworm oil-in-water emulsion composition C4 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C4-2 was used.

[0162] Example 8 A silkworm oil-in-water emulsion composition C5 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C5-2 was used.

[0163] Example 9 Silkworm oil-in-water emulsion composition C7 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C7-2 was used.

[0164] Example 10 Silkworm oil-in-water emulsion composition C8 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C8-2 was used.

[0165] Example 11 A silkworm oil-in-water emulsion composition C9 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C9-2 was used.

[0166] Example 12 A silkworm oil-in-water emulsion composition C10 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C10-2 was used.

[0167] (Comparative Example 1) Silkworm oil-in-water emulsion composition A1 was obtained in the weight ratio shown in Table 4 in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion A1 was used.

[0168] (Comparative Example 2) Silkworm oil-in-water emulsion composition A4 was obtained in the weight ratio shown in Table 4 in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion A4 was used.

[0169] (Comparative Example 3) Silkworm oil-in-water emulsion composition B1-1 was obtained in the weight ratio shown in Table 4 in the same manner as in Example 1, except that silkworm supernatant B1-1 was used.

[0170] Comparative Example 4 Silkworm oil-in-water emulsion composition B1-10 was obtained in the weight ratio shown in Table 4 in the same manner as in Example 1, except that silkworm supernatant B1-10 was used.

[0171] (Comparative Example 5) Silkworm oil-in-water emulsion composition B3 was obtained in the weight ratio shown in Table 4 in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion B3 was used.

[0172] (Comparative Example 6) Silkworm oil-in-water emulsion composition C3 was obtained in the weight ratio shown in Table 4 in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C3 was used.

[0173] (Comparative Example 7) Silkworm oil-in-water emulsion composition C6 having the weight ratio shown in Table 4 was obtained in the same manner as in Example 1, except that the silkworm-derived particle aqueous dispersion C6-2 was used.

[0174] (Comparative Example 8) An oil-in-water emulsion composition D1 having the weight ratio shown in Table 4 was obtained in the same manner as in Example 1, except that ion-exchanged water was used as the aqueous phase component.

[0175] (Comparative Example 9) An oil-in-water emulsion composition D2 having the weight ratio shown in Table 4 was obtained in the same manner as in Example 1, except that an aqueous citric acid solution (pH 4) was used as the aqueous phase component.

[0176] (Comparative Example 10) An oil-in-water emulsion composition D3 having the weight ratio shown in Table 4 was obtained in the same manner as in Example 1, except that an aqueous sodium hydroxide solution (pH 10) was used as the aqueous phase component.

[0177] [Table 3]

[0178] [Table 4]

[0179] [Evaluation of aqueous dispersions of silkworm-derived particles, silkworm powder, and their preparation processes] (Evaluation of aqueous dispersion of silkworm-derived particles) Table 5 shows the measurement results of the surface tension of the silkworm particle water dispersion C10-2 according to Example 12 and the silkworm particle water dispersion A1 according to Comparative Example 1, as well as the interfacial tension between these dispersions and castor oil.

[0180] [Table 5]

[0181] Next, Table 6 shows the measurement results of the surface tension of the supernatant in the washing step of the silkworm particle aqueous dispersion B1, which is the aqueous phase of Example 3, and the silkworm particle aqueous dispersion C7-2, which is the aqueous phase of Example 9.

[0182] [Table 6]

[0183] As shown in Table 6, the surface tension of the supernatant increases with the number of centrifugal washes, indicating that repeated washing reduces the amount of water-soluble surfactants eluted into the washing solvent, water. Furthermore, as shown in Table 5, although the solids concentration of silkworm particle aqueous dispersion C10-2 is higher, the surface tension of silkworm particle aqueous dispersion C10-2 after centrifugal washing is higher than that of silkworm particle aqueous dispersion A1, which was not subjected to centrifugal washing. This also indicates that the water-soluble surfactants were removed by centrifugal washing. Next, the zeta potential measurement results for the silkworm particle aqueous dispersion B1 are shown in Figure 11. From the results in Figures 4 and 11, it was found that the isoelectric point of the silkworm particles before washing (silkworm particle aqueous dispersion A1) was 3.70, and the isoelectric point of the silkworm particles after washing (silkworm particle aqueous dispersion B1) was 3.76, which means that the isoelectric points were the same before and after washing.

[0184] (Size evaluation of silkworm-derived particles) First, optical microscope photographs of silkworm particle aqueous dispersions A1, A2, and A4 are shown in Figures 12, 13, and 14. In Figure 14, aggregation due to the influence of surface potential is seen more clearly than in Figures 12 and 15, and it was found that the particle size was larger when the particles were not disintegrated. Next, Table 7 shows the results of measuring the average particle size of silkworm particles in an aqueous medium for silkworm-derived particle aqueous dispersion A1, silkworm-derived particle aqueous dispersion C1 (before washing), and silkworm-derived particle aqueous dispersion C4.

[0185] [Table 7]

[0186] The average particle size of silkworm particles in aqueous media tended to become smaller in the order of silkworm-derived particle aqueous dispersions A1, C1 (before washing), and C4. Crushing using an agate mortar and separating the supernatant (removing relatively large particles that settle by their own weight and separating only the small floating particles) were shown to be effective in reducing the particle size of silkworm particles.

[0187] An SEM image of the silkworm particle powder obtained by drying the silkworm particle aqueous dispersion C4-1 is shown in Figure 15. It can be seen that the silkworm particle powder is finer than that of Figure 1. Furthermore, optical microscope images of the prepared silkworm particle aqueous dispersion C1 (before washing) and silkworm particle aqueous dispersion C4-1 are shown in Figures 16 and 17, respectively. It can be seen that the size (major axis of the particles) of the silkworm particle powder in Figure 16 (unwashed silkworm particles that have been subjected to a crushing treatment) is finer than that in Figure 12 (unwashed silkworm particles), and that the size (major axis of the particles) of the silkworm particle powder in Figure 17 (silkworm particles that have been crushed and have had the sediment removed and the supernatant separated) is finer than that in Figure 16.

[0188] (Composition analysis of silkworm powder) Table 8 shows the results of moisture content, organic elemental analysis (CHNS), and quantitative amino acid analysis (protein content in BSA equivalent, free amino acid content) for Silkworm powder C10 (washed silkworm powder), Silkworm powder (silkworm powder before washing), and Silkworm powder C10-1 (silkworm water-soluble substance).

[0189] [Table 8]

[0190] In particular, when looking at BSA-equivalent protein, silkworm powder C10 (washed silkworm powder) shows a higher value than silkworm powder (silkworm powder before washing). Although 12% by weight of protein was confirmed to have been eluted in silkworm powder C10-1, it is easy to assume that water-soluble substances other than protein were also eluted. Considering that the CHNS content was about the same before and after washing, it is assumed that water-soluble substances containing inorganic elements were also eluted.

[0191] [Evaluation of oil-in-water emulsion composition] (Pickering emulsion forming ability) The presence or absence of interfacial adsorption of solid particles, which is important in the formation of Pickering emulsions, and the surface coverage were evaluated visually. The details of the evaluation are as follows. For the above-mentioned Examples and Comparative Examples, the possibility of emulsification, the emulsion type, and the stability of the emulsions after one day of storage are shown in Tables 9 and 10. Microscopic images of the prepared emulsions are shown in Figures 18 to 34. From the microscopic images in Figures 8 to 10 and Figures 18 to 34, the degree of adsorption of silkworm particles to the oil-water interface was evaluated using the following five-level scale, and the results are shown in Tables 9 and 10.

[0192] N: No adsorption of solid particles to the oil-water interface. +: It is unclear whether solid particles are adsorbed to the oil-water interface. ++: Although some adsorption of solid particles at the oil-water interface was confirmed (the outer edge was uneven), the adsorption state was sparse. +++: Adsorption of solid particles to the oil-water interface was confirmed (the outer edge was uneven), and the adsorption state was dense. ++++: Solid particles are observed adsorbed to the oil-water interface (including unevenness on the outer edge), and the adsorption state is so dense that the light transmittance decreases.

[0193] [Table 9]

[0194] [Table 10]

[0195] As can be seen from Tables 9 and 10, in cases where interfacial adsorption of solid particles (silkworm-derived particles) was confirmed by microscopic observation, an O / W emulsion was formed, and it was also found that storage stability differed depending on the degree of interfacial adsorption (coarseness or density) of the solid particles. When denser adsorption was confirmed, coalescence of oil droplets could be physically suppressed, and therefore stability was improved compared to those with no solid particle adsorption, and even more improved than those with loosely adsorbed solid particles.

[0196] The results shown in Tables 9 and 10 indicate that interfacial adsorption of solid particles is more promoted under conditions where the pH of the aqueous phase is low and electrostatic repulsion between oil droplets and silkworm particles is suppressed, or in compositions in which water-soluble substances or water-soluble surfactants have been removed by centrifugal washing of silkworm-derived particles with water, or in compositions in which the size of silkworm-derived particles has been reduced, or in combinations thereof.

[0197] (Long term stability) Example 12 (Silkworm Emulsion Composition C10) was stored in a refrigerator (4°C) from the day of preparation until three months later, and the emulsion stability was evaluated. The emulsion stability and the change over time in the average particle size of the oil droplets, which are the internal phase of the oil-in-water emulsion, are shown in Table 11. The emulsion stability was evaluated by visually observing the side of the container according to the following criteria. ○: Oil phase separation occurred ×: No oil phase separation

[0198] [Table 11]

[0199] The results shown in Tables 9, 10, and 11 indicate that the oil-in-water emulsion composition in which solid particles (silkworm-derived particles) were densely adsorbed to the oil-water interface did not show separation of the oil phase components even after long-term storage of 3 months, and the average particle size of the oil droplets did not change significantly, demonstrating good storage stability.

[0200] [Preparation of aqueous dispersion of cricket-derived particles] (Preparation Example 18) The cricket powder was crushed for 5 minutes using an agate mortar. 4 parts by weight of this crushed cricket powder and 96 parts by weight of ion-exchanged water were dispensed into containers in the weight ratios shown in Table 12. These were stirred using a homogenizer at 12,000 rpm for 10 minutes to obtain a cricket-derived particle aqueous dispersion A1.

[0201] (Preparation Example 19) A water dispersion A2 of cricket-derived particles was obtained in the same manner as in Preparation Example 18, except that cricket powder, ion-exchanged water, and an aqueous citric acid solution were used in the weight ratios and pH of 4 shown in Table 12.

[0202] (Preparation Example 20) A water dispersion A3 of cricket-derived particles was obtained in the same manner as in Preparation Example 18, except that cricket powder, ion-exchanged water, and an aqueous sodium hydroxide solution were used in the weight ratios shown in Table 12 and at a pH of 10.

[0203] (Preparation Example 21) The cricket powder was crushed for 5 minutes using an agate mortar. 10 parts by weight of this crushed cricket powder and 90 parts by weight of ion-exchanged water were dispensed into a container and stirred using a homogenizer at 12,000 rpm for 10 minutes to obtain cricket-derived particle aqueous dispersion C1 (before washing). This cricket-derived particle aqueous dispersion (before washing) was first centrifuged using a centrifuge (CF16RX II, HITACHI) at 15,000 rpm for 10 minutes under brake-free conditions, and the supernatant was removed. An equal amount of ion-exchanged water was then added to the container containing the sediment and stirred. Next, the container was centrifuged again, and the supernatant was removed. Ion-exchanged water was then added to the container and stirred. This centrifugal washing procedure was repeated a total of 40 times to obtain cricket particle aqueous dispersion C0. Furthermore, a predetermined amount of citric acid solution and ion-exchanged water were added to adjust the pH to 4, to obtain an aqueous dispersion C1 of cricket-derived particles having the composition shown in Table 12. The supernatants removed after the 10th, 20th, and 40th centrifugal washings are referred to as cricket supernatant C1-10, cricket supernatant C1-20, and cricket supernatant C1-40, respectively.

[0204] (Preparation Example 22) After the crushed cricket powder was washed with water, the pH was finally adjusted to 10 using an aqueous sodium hydroxide solution. In the same manner as in Preparation Example 21, an aqueous dispersion C2 of cricket-derived particles having the weight ratio shown in Table 12 was obtained.

[0205] (Preparation Example 23) A water dispersion C3 of cricket-derived particles was obtained in the same manner as in Preparation Example 21, except that the weight ratio of the solid content derived from silkworm powder was set to that shown in Table 12.

[0206] (Preparation Example 24) A water dispersion C4 of cricket-derived particles was obtained in the same manner as in Preparation Example 21, except that the weight ratio of the solid content derived from silkworm powder was set to that shown in Table 12.

[0207] (Preparation Example 25) A water dispersion C5 of cricket-derived particles was obtained in the same manner as in Preparation Example 21, except that the weight ratio of the solid content derived from silkworm powder was set to that shown in Table 12.

[0208] [Table 12]

[0209] [Preparation of oil-in-water emulsion composition] Example 13 The cricket-derived particle water dispersion A1 and castor oil were dispensed into containers in the weight ratios shown in Table 13. These were stirred using a homogenizer at room temperature at 12,000 rpm for 2 minutes to obtain a cricket oil-in-water emulsion composition A1.

[0210] Example 14 A cricket oil-in-water emulsion composition A2 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion A2 was used.

[0211] Example 15 A cricket oil-in-water emulsion composition C1 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion C1 was used.

[0212] Example 16 A cricket oil-in-water emulsion composition C3 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion C3 was used.

[0213] Example 17 A cricket oil-in-water emulsion composition C4 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion C4 was used.

[0214] Example 18 A cricket oil-in-water emulsion composition C5 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion C5 was used.

[0215] (Comparative Example 11) A cricket oil-in-water emulsion composition A3 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion A3 was used.

[0216] (Comparative Example 12) A cricket oil-in-water emulsion composition C2 was obtained in the same manner as in Example 13, except that the cricket-derived particle aqueous dispersion C2 was used.

[0217] [Table 13]

[0218] [Evaluation of cricket-derived particle aqueous dispersion, cricket powder, and its preparation process] (Evaluation of aqueous dispersion of cricket-derived particles) Table 14 shows the results of measuring the surface tension of the supernatants (cricket supernatants C1-10, C1-20, and C1-40) during washing in the preparation process of cricket particle aqueous dispersion C1, which is the aqueous phase of Example 15. Table 14 shows that the surface tension of the supernatants increases with the number of centrifugal washes, indicating that repeated washing reduces the amount of water-soluble surfactant components eluted into the washing solvent, water. In other words, it can be said that it is possible to prepare cricket-derived particle aqueous dispersion C1 from which at least a portion of the water-soluble surfactant components have been removed by the washing procedure.

[0219] [Table 14]

[0220] (Size evaluation of cricket-derived particles) The average particle size (Dv) of the cricket particles in the aqueous medium of the cricket-derived particle aqueous dispersion A1 was 54 μm±56 μm. Optical microscope photographs of cricket-derived particle aqueous dispersions A1, A2, and A3 are shown in Figures 36, 37, and 38, respectively. Due to the influence of the zeta potential, in the undisintegrated state, cricket-derived particle aqueous dispersion A2 at pH 4 showed some aggregation compared to cricket-derived particle aqueous dispersion A3 at pH 10. The zeta potential measurement results for the cricket particle aqueous dispersion C0 are shown in Figure 35. From the results of Figures 5 and 35, it was found that the isoelectric points before and after washing were almost the same.

[0221] (Composition analysis of cricket powder) The cricket particle aqueous dispersion C1 and the cricket supernatant C1-1 were freeze-dried to obtain cricket powder C1 and cricket powder C1-1, respectively. The water content, organic elemental analysis (CHNS), and amino acid quantitative analysis (BSA-equivalent protein content and free amino acid content) of cricket powder C1 (water-washed cricket powder), cricket powder (cricket powder before washing), and cricket powder C1-1 (cricket water-soluble substance) were analyzed. The results are shown in Table 15.

[0222] [Table 15]

[0223] In particular, the BSA-equivalent protein content is higher in cricket powder C1 (washed cricket powder) than in cricket powder (cricket powder before washing). Considering the results shown in Tables 14 and 15, it can be said that at least a portion of the water-soluble substances (including water-soluble surfactants) are removed by the washing procedure using water, resulting in an increase in the concentration of insoluble proteins that are not dissolved in water.

[0224] (Pickering emulsion forming ability) The presence or absence of interfacial adsorption of solid particles, which is important in the formation of Pickering emulsions, and the surface coverage were evaluated visually. The details of the evaluation are as follows. For the above-mentioned Examples and Comparative Examples, the possibility of emulsification, the emulsion type, and the stability of the emulsion after one day of storage are shown in Table 16. Microscopic images of the prepared emulsions are shown in Figures 39 to 43. From these microscopic images, the degree of adsorption of the cricket-derived particles to the oil-water interface was evaluated using the following five-point scale, and the results are shown in Table 16.

[0225] N: No adsorption of solid particles to the oil-water interface. +: It is unclear whether solid particles are adsorbed to the oil-water interface. ++: Although some adsorption of solid particles at the oil-water interface was confirmed (the outer edge was uneven), the adsorption state was sparse. +++: Adsorption of solid particles to the oil-water interface was confirmed (the outer edge was uneven), and the adsorption state was dense. ++++: Solid particles are observed adsorbed to the oil-water interface (including unevenness on the outer edge), and the adsorption state is so dense that the light transmittance decreases.

[0226] [Table 16]

[0227] As can be seen from Table 16, in cases where interfacial adsorption of solid particles (cricket-derived particles) was confirmed by microscopic observation, an O / W emulsion was formed, and it was found that storage stability differed depending on the degree of interfacial adsorption (coarseness or density) of the solid particles. When denser adsorption was confirmed, coalescence of the oil droplets could be physically suppressed, resulting in improved stability compared to emulsions with no solid particle adsorption, and even improved stability compared to emulsions with loosely adsorbed solid particles.

[0228] The results shown in Table 16 indicate that interfacial adsorption of solid particles is more promoted under conditions where the pH of the aqueous phase is low and electrostatic repulsion between the oil droplets and the cricket-derived particles is suppressed, or in compositions in which water-soluble substances or water-soluble surfactants have been removed by centrifugal washing of the cricket-derived particles with water, or in compositions in which the size of the cricket-derived particles has been reduced, or in combinations thereof.

[0229] (Long term stability) Example 15 (cricket emulsion composition C1) was stored in a refrigerator (4°C) from the day of preparation until 3 months later, and the emulsion stability was evaluated over time. The emulsion stability and the change over time in the average particle size of the oil droplets, which are the internal phase of the oil-in-water emulsion, are shown in Table 17. The emulsion stability was evaluated by visually observing the side of the container according to the following criteria. ○: Oil phase separation occurred. ×: No oil phase separation.

[0230] [Table 17]

[0231] The results in Tables 16 and 17 show that the oil-in-water emulsion composition in which solid particles (cricket-derived particles) are densely adsorbed to the oil-water interface shows good storage stability with no separation of the oil phase components even after long-term storage of 3 months.

[0232] [Preparation of water dispersion of grasshopper-derived particles] (Preparation Example 26) The grasshopper powder was crushed for 5 minutes using an agate mortar. 4 parts by weight of this crushed grasshopper powder and 96 parts by weight of ion-exchanged water were dispensed into a container. This mixture was subjected to ultrasonic treatment for 20 minutes using a Bransonic tabletop ultrasonic cleaner (Bransonic, M2800-J) to obtain a grasshopper-derived particle aqueous dispersion A1.

[0233] (Preparation Example 27) A water dispersion A2 of grasshopper-derived particles was obtained by carrying out the same procedure as in Preparation Example 26, except that the mixture was adjusted to pH 4 using crushed grasshopper powder, ion-exchanged water, and an aqueous citric acid solution.

[0234] (Preparation Example 28) A water dispersion A3 of locust-derived particles was obtained by carrying out the same procedure as in Preparation Example 26, except that the mixture was adjusted to pH 10 using powdered locust powder, ion-exchanged water, and an aqueous sodium hydroxide solution.

[0235] (Preparation Example 29) The grasshopper powder was crushed for 5 minutes using an agate mortar. 10 parts by weight of the crushed grasshopper powder and 90 parts by weight of ion-exchanged water were dispensed into a container. This was stirred using a homogenizer at 12,000 rpm for 10 minutes to obtain a water dispersion of grasshopper-derived particles. This grasshopper-derived particle aqueous dispersion was first centrifuged at 15,000 rpm for 10 minutes using a centrifuge (CF16RX II, HITACHI) under brake-free conditions. After removing the supernatant, the same amount of ion-exchanged water as the removed supernatant was added to the container containing the sediment and stirred. Next, the container was centrifuged again, the supernatant was removed, and ion-exchanged water was added to the container and stirred. This centrifugal washing procedure was repeated a total of 25 times to obtain grasshopper particle aqueous dispersion C0. Furthermore, a predetermined amount of citric acid aqueous solution and ion-exchanged water were added to this to adjust the pH to 4 and the weight ratio shown in Table 18 to obtain grasshopper-derived particle aqueous dispersion C1. The supernatants removed after the 1st, 10th, 20th, and 25th centrifugal washes are referred to as grasshopper supernatant C1-1, grasshopper supernatant C1-10, grasshopper supernatant C1-20, and grasshopper supernatant C1-25, respectively.

[0236] (Preparation Example 30) A water dispersion C2 of grasshopper-derived particles was obtained in the same manner as in Preparation Example 29, except that the pH was adjusted to 10 using an aqueous sodium hydroxide solution, so as to have the weight ratio shown in Table 18.

[0237] (Preparation Example 31) A water dispersion C3 of grasshopper-derived particles was obtained by preparing it in the same manner as in Preparation Example 29, except that it was prepared so as to have the weight ratio shown in Table 18.

[0238] [Table 18]

[0239] [Preparation of oil-in-water emulsion composition] Example 19 The grasshopper-derived particle water dispersion A1 and castor oil were dispensed into containers in the weight ratios shown in Table 19. This was stirred at 12,000 rpm at room temperature for 2 minutes using a homogenizer to obtain a grasshopper oil-in-water emulsion composition A1.

[0240] Example 20 A locust oil-in-water emulsion composition A2 was obtained in the same manner as in Example 20, except that the locust-derived particle aqueous dispersion A2 was used.

[0241] Example 21 A locust oil-in-water emulsion composition C1 was obtained in the same manner as in Example 20, except that the locust-derived particle aqueous dispersion C1 was used.

[0242] Example 22 A locust oil-in-water emulsion composition C3 was obtained in the same manner as in Example 20, except that the locust-derived particle aqueous dispersion C3 was used.

[0243] (Comparative Example 13) A locust oil-in-water emulsion composition A3 was obtained in the same manner as in Example 20, except that the locust-derived particle aqueous dispersion A3 was used.

[0244] (Comparative Example 14) A locust oil-in-water emulsion composition C2 was obtained in the same manner as in Example 20, except that the locust-derived particle aqueous dispersion C2 was used.

[0245] [Table 19]

[0246] [Evaluation of water dispersions of grasshopper-derived particles, grasshopper powder, and their preparation processes] (Evaluation of water dispersion of grasshopper-derived particles) Table 20 shows the measurement results of the surface tension of the supernatants (locust supernatants C1-10, C1-20, C1-25) during water washing in the preparation process of locust particle aqueous dispersion C1, which is the aqueous phase of Example 15. The results shown in Table 20 indicate that the surface tension of the supernatant increases with the number of centrifugal washes, indicating that repeated washing reduces the amount of water-soluble surfactant eluted into the washing solvent (water). In other words, it is possible to prepare an aqueous dispersion C1 of grasshopper-derived particles from which at least a portion of the water-soluble surfactant has been removed by the washing procedure. Next, the zeta potential measurement results for the grasshopper particle aqueous dispersion C0 are shown in Figure 44. From the results of Figures 6 and 44, it was found that the isoelectric points before and after washing were almost the same.

[0247] [Table 20]

[0248] (Size evaluation of grasshopper-derived particles) The average particle size (Dv) of the grasshopper particles in the water medium of the grasshopper-derived particle aqueous dispersion A1 was 125 μm±129 μm. Optical microscope photographs of the grasshopper particle water dispersions A1, A2, and A3 are shown in Figures 45, 46, and 47, respectively. Due to the influence of the zeta potential, in the undisintegrated state, the grasshopper particle water dispersion A2 at pH 4 showed some aggregation compared to the grasshopper particle water dispersion A1 at pH 5.8 and the grasshopper particle water dispersion A3 at pH 10.

[0249] (Composition analysis of grasshopper powder) The grasshopper particle aqueous dispersion C1 and the grasshopper supernatant C1-1 were freeze-dried to obtain grasshopper powder C1 and grasshopper powder C1-1, respectively. The results of water content, organic elemental analysis (CHNS), and amino acid quantitative analysis (BSA equivalent protein content, free amino acid content) of the grasshopper powder C1 (water-washed grasshopper powder), grasshopper powder (grasshopper powder before water-washing), and grasshopper powder C1-1 (grasshopper water-soluble substance) according to Example 21 are shown in Table 21.

[0250] [Table 21]

[0251] In particular, when we look at the BSA-equivalent protein, the value is higher in grasshopper powder C1 (water-washed grasshopper powder) than in grasshopper powder (grasshopper powder before washing). Considering the results shown in Tables 20 and 21, it can be said that at least a portion of the water-soluble substances (including water-soluble surfactants) are removed by the washing operation with water, and as a result, the concentration of insoluble proteins that are not dissolved in water increases.

[0252] [Evaluation of oil-in-water emulsion composition] (Pickering emulsion forming ability) The presence or absence of interfacial adsorption of solid particles, which is important in the formation of Pickering emulsions, and the surface coverage were evaluated visually. Details of the evaluation are as follows. For the above-mentioned Examples and Comparative Examples, the possibility of emulsification, emulsion type, and stability of the emulsion after one day of storage are shown in Table 22. Microscopic images of the prepared emulsions are also shown in Figures 48 to 52. From these microscopic images, the degree of adsorption of grasshopper-derived particles to the oil-water interface was evaluated using the following five-point scale, and the results are shown in Table 22. N: No adsorption of solid particles to the oil-water interface +: It is unclear whether solid particles are adsorbed to the oil-water interface. ++: Although some adsorption of solid particles at the oil-water interface was confirmed (the outer edge was uneven), the adsorption state was sparse. +++: Adsorption of solid particles to the oil-water interface was confirmed (the outer edge was uneven), and the adsorption state was dense. ++++: Solid particles are observed adsorbed to the oil-water interface (including unevenness on the outer edge), and the adsorption state is so dense that the light transmittance decreases.

[0253] [Table 22]

[0254] As can be seen from the results shown in Table 22, in cases where interfacial adsorption of solid particles (locust-derived particles) was confirmed by microscopic observation, an O / W emulsion was formed, and it was also found that storage stability differed depending on the degree of interfacial adsorption (coarseness or density) of the solid particles. When denser adsorption was confirmed, coalescence of the oil droplets was physically suppressed, resulting in improved stability compared to those without solid particle adsorption, and even improved stability compared to those with loose solid particle adsorption. It is also found that interfacial adsorption of solid particles is more promoted in pH ranges where the electrostatic repulsion between oil droplets in the aqueous phase and grasshopper particles is relatively suppressed, in compositions in which water-soluble substances or water-soluble surfactants have been removed by centrifugal washing of grasshopper-derived particles with water, in compositions in which the size of grasshopper-derived particles has been made smaller, or in combinations of these.

[0255] (Long term stability) Example 21 (grasshopper emulsion composition C1) was stored in a refrigerator (4°C) from the day of preparation until 3 months later, and the emulsion stability was evaluated over time. The emulsion stability and the measured values ​​of the average particle size of the oil droplets, which are the internal phase of the oil-in-water emulsion, are shown in Table 23. The emulsion stability was evaluated by visually observing the side of the container according to the following criteria. ○: Oil phase separation occurred ×: No oil phase separation

[0256] [Table 23]

[0257] The results shown in Tables 22 and 23 indicate that the oil-in-water emulsion composition, in which solid particles (grasshopper-derived particles) are densely adsorbed to the oil-water interface, exhibits good storage stability with no separation of the oil phase components even after long-term storage of 3 months. [Industrial Applicability]

[0258] According to the present invention, it is possible to provide an emulsion composition that uses raw materials that are suitable from the viewpoints of addressing milk allergies and being environmentally friendly, and that also has excellent emulsion stability.

Claims

1. Contains water, oil and solid particles, the solid particles are present at the interface between the water and the oil, at least a portion of the solid particles are insect proteins; An oil-in-water emulsion composition, wherein the pH of the aqueous phase or the aqueous dispersion containing the solid particles is 7.5 or less.

2. 2. The oil-in-water emulsion composition according to claim 1, wherein the surface tension of the aqueous phase is 32 mN / m or more.

3. 2. The oil-in-water emulsion composition according to claim 1, wherein at least a portion of the solid particles are at least one protein selected from the group consisting of silkworm protein, cricket protein, and grasshopper protein.

4. Contains water, oil and solid particles, the solid particles are present at the interface between the water and the oil, at least a portion of the solid particles are insect proteins; An oil-in-water emulsion composition, wherein the surface tension of the aqueous phase is 32 mN / m or more.

5. The oil-in-water emulsion composition according to claim 4 , wherein the pH of the aqueous phase or the aqueous dispersion containing the solid particles is 7.5 or less.

6. 5. The oil-in-water emulsion composition according to claim 4, wherein at least a portion of the solid particles are at least one protein selected from the group consisting of silkworm protein, cricket protein, and grasshopper protein.

7. A method for producing an oil-in-water emulsion composition comprising water, oil, and solid particles, the solid particles being present at an interface between the water and the oil, comprising: The method of manufacturing the solid particles comprises using an insect protein obtained after removing at least a portion of the amphiphilic substance from an insect protein raw material.

8. The production method according to claim 7, further comprising adjusting the pH of the protein aqueous dispersion obtained by stirring the insect protein and the water to 7.5 or less, and then stirring the protein aqueous dispersion and the solid particles.

9. The method according to claim 7, wherein at least a portion of the solid particles is at least one protein selected from the group consisting of silkworm protein, cricket protein, and grasshopper protein.

10. A food product comprising the oil-in-water emulsion composition according to any one of claims 1 to 6.

11. A milk replacer comprising the oil-in-water emulsion composition according to any one of claims 1 to 6.

12. A pharmaceutical product comprising the oil-in-water emulsion composition according to any one of claims 1 to 6.

13. A cosmetic comprising the oil-in-water emulsion composition according to any one of claims 1 to 6.

14. A personal care product comprising the oil-in-water emulsion composition according to any one of claims 1 to 6.

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