Plant milk for foaming and method for producing plant milk for foaming

Abstract

Provided is a plant milk for foaming, which contains a plant milk and a protein material having the following properties (A) and (B). (A) After an aqueous solution of the protein material in an amount of 20 mass% in terms of crude protein contained in the protein material is heated at 80 DEG C for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa * s at 25 DEG C. (B) The protein material has a 0.22 M TCA solubilization rate of 10% to 95%.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Japanese Patent Application No. 2024-033322 filed with the Japan Patent Office on March 5, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to foaming plant milks and methods of making foaming plant milks. Background Art

[0004] The use of plant-based milks, such as soy milk, as dairy alternatives is growing due to climate change, including global warming, the growing influence of millennials on purchasing decisions due to their growing environmental awareness, awareness of animal welfare, and health concerns related to cholesterol accumulation when consuming animal protein. However, plant-based milks have poorer foaming stability than dairy milk. Consequently, even when frothing plant-based milk is added to coffee, the foam tends to disappear.

[0005] As a method for imparting foamability, techniques using emulsifiers or stabilizers are known. For example, a method for adding various emulsifiers or foaming proteins to milk to prepare a foamable beverage is disclosed (Japanese Patent Application Laid-Open No. 10-295339). Similarly, a method for adding an emulsifier with an HLB of 14 or greater is disclosed (Japanese Patent Application Laid-Open No. 2009-50259), as well as a method for adding casein, soy protein, microcrystalline cellulose, or carrageenan (Japanese Patent Application Laid-Open No. 60-87775).

[0006] As a technology for using an emulsifier or stabilizer instead of milk in nut milk, for example, a technology of adding high acyl gellan gum, gum arabic, or guar gum is disclosed (Japanese Patent Publication No. 2019-512211).

[0007] However, the technology disclosed in Japanese Patent Application Publication No. 2019-512211 is about improving the mouthfeel, and does not disclose technology related to foaming properties.

[0008] Furthermore, in order to improve the foaming properties of soy milk, a technology of adding sucrose fatty acid esters, glycerin fatty acid esters, or organic acid monoglycerides having an HLB of 8 or higher to soy milk has been disclosed (Japanese Patent No. 6390071).

[0009] However, the technology disclosed in Japanese Patent No. 6390071 is a technology specifically for an emulsifier, and does not disclose a technology regarding foaming properties other than an emulsifier. Summary of the Invention

[0010] The foamable plant milk of this embodiment contains plant milk and a protein material having the following properties (A) and (B). (A) After heating an aqueous solution of the protein material containing 20% ​​by mass, calculated as crude protein contained in the protein material, at 80°C for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25°C. (B) The protein material has a 0.22M TCA solubility of 10% to 95%. DETAILED DESCRIPTION

[0011] In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, it may be apparent that one or more embodiments can be practiced without these specific details.

[0012] The present embodiment aims to provide foamed plant milk having good foaming properties and foaming stability by foaming (foaming) using a foamer, etc. Another aim of the present embodiment is to provide foamed plant milk for foaming.

[0013] The present inventors conducted extensive research to address the above-mentioned challenges. As a result, they discovered that foamed plant milk prepared using a protein material with specific properties exhibits excellent foaming properties and foam stability. This led to the completion of the plant milk of this embodiment.

[0014] That is, the vegetable milk for foaming according to the present embodiment is the following vegetable milk for foaming (1) to (4).

[0015] (1) A plant milk for foaming, comprising plant milk and a protein material having the following properties (A) and (B).

[0016] (A) After heating an aqueous solution of the protein material containing 20% ​​by mass, calculated as crude protein contained in the protein material, at 80° C. for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25° C.

[0017] (B) The solubility rate of the above-mentioned protein material in 0.22 M TCA is 10% to 95%.

[0018] (2) The vegetable milk for foaming according to (1), wherein, in the property (A), the viscosity is 10,000 mPa·s or less.

[0019] (3) The plant milk for foaming according to (1), wherein, in the above-mentioned property (B), the above-mentioned 0.22M TCA solubility rate of the above-mentioned protein material is 30% to 95%.

[0020] (4) The plant milk for foaming according to (1), wherein, in the above-mentioned property (A), the viscosity is 10,000 mPa·s or less, and in the above-mentioned property (B), the above-mentioned 0.22 M TCA solubility rate of the above-mentioned protein material is 30% to 95%.

[0021] The plant milk beverage of this embodiment is the following plant milk beverage (5).

[0022] (5) A plant milk beverage covered with (placed on) foamed plant milk prepared by foaming any one of the plant milks for foaming described in (1) to (4) above.

[0023] The method for producing vegetable milk for foaming according to the present embodiment is the method for producing vegetable milk for foaming according to the following (6).

[0024] (6) A method for producing plant milk for foaming, comprising the step of emulsifying plant milk and a raw material containing a protein material having the following properties (A) and (B).

[0025] (A) After heating an aqueous solution of the protein material containing 20% ​​by mass, calculated as crude protein contained in the protein material, at 80° C. for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25° C.

[0026] (B) The solubility rate of the above-mentioned protein material in 0.22 M TCA is 10% to 95%.

[0027] The method for producing foamed vegetable milk according to the present embodiment is the method for producing foamed vegetable milk according to the following (7).

[0028] (7) A method for producing foamed vegetable milk, comprising the step of foaming any one of the foaming vegetable milks of (1) to (4) above.

[0029] The method for foaming plant milk according to the present embodiment is the method for foaming plant milk according to the following (8).

[0030] (8) A method for foaming plant milk, comprising the step of foaming any one of the plant milks for foaming described in (1) to (4).

[0031] According to the present embodiment, foamed vegetable milk having good foaming properties and foaming stability, and foamed vegetable milk for foaming can be provided.

[0032] (Use plant milk for foaming)

[0033] The vegetable milk for foaming in this embodiment refers to vegetable milk for foaming (frothing) using a steamer, a foamer, or the like.

[0034] The plant milk for foaming of this embodiment contains a protein material having the following properties (A) and (B).

[0035] (A) After heating an aqueous solution of the protein material at 20% by mass, calculated as crude protein contained in the protein material, at 80° C. for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25° C.

[0036] (B) The solubility rate of the above-mentioned protein material in 0.22 M TCA is 10% to 95%.

[0037] The foamed vegetable milk obtained by foaming the vegetable milk for foaming according to the present embodiment using a steamer, a foamer, or the like has excellent foaming properties and foaming stability.

[0038] (Plant Milk)

[0039] The plant milk for foaming of this embodiment contains plant milk. The plant milk used in this embodiment refers to milk prepared by extracting the components contained in the plant as the raw material with an aqueous solvent. Specifically, it is milk based on raw materials such as beans, seeds or grains. The plant milk for foaming of this embodiment can use the aqueous solvent extract (aqueous solution) directly. In addition, a concentrated aqueous solvent extract obtained by removing part of the water from the above-mentioned aqueous solvent extract can also be used. Furthermore, the temporarily dried aqueous solvent extract can also be dispersed in water for use.

[0040] As soy-based milk (soy milk), slurry-like soy milk prepared by finely grinding okara without removing it from soy milk can also be used.

[0041] Examples of legumes include soybeans, lupines, mung beans, red beans, broad beans, peas, chickpeas, kidney beans, lentils, lentils, and cowpeas. Examples of seeds include sesame, canola, coconut, almonds, walnuts, cashews, and hazelnuts. Examples of grains include corn, buckwheat, wheat, barley, oats, and rice.

[0042] Examples of preferred legumes are soybeans, mung beans, beans, peas and chickpeas, examples of preferred seeds are coconut and almonds, and examples of preferred cereals are oats.

[0043] Examples of plant milk include soy milk, low-fat soy milk, pea soy milk, mung bean milk, oat milk, almond milk, and coconut milk.

[0044] (Protein material)

[0045] The protein material used in the present embodiment has a low viscosity after heating (hereinafter referred to as viscosity after heating). In the determination of viscosity after heating, first, a protein material aqueous solution is prepared in a manner such that the concentration of crude protein contained in the protein material becomes 20% by mass. Next, the prepared aqueous solution is heated at 80°C for 30 minutes. Then, the viscosity of the heated aqueous solution is measured at 25°C. Thus, the viscosity after heating can be measured. The viscosity after heating is less than 100,000 mPa·s, preferably less than 10,000 mPa·s, less than 5,000 mPa·s, less than 1,000 mPa·s or less than 500 mPa·s, more preferably less than 200 mPa·s or less than 100 mPa·s.

[0046] In addition, the protein material used in the present embodiment has a molecular weight of a certain size. The molecular weight is defined by the TCA solubility rate. In the present embodiment, the TCA solubility rate is defined as the ratio of the mass of crude protein dissolved in 0.22M TCA to the mass of total crude protein. The TCA solubility rate of the present protein material can be set to 10-95%, preferably 30%-95%, 35-90%, 40-85%, 45-80% or 50-80%. If the TCA solubility rate is too low, there is a tendency for the viscosity to increase after heating. Therefore, a too low TCA solubility rate is sometimes not suitable. In addition, if the TCA solubility rate is too low, the transmittance is sometimes reduced.

[0047] On the other hand, if the TCA solubilization rate is too high, the amount of protein that contributes to emulsification will decrease. As a result, a large amount of protein material will need to be added. Therefore, the degree of freedom in addition may be reduced.

[0048] The protein material used in the present embodiment preferably has an NSI (Nitrogen Solubility Index) of 80 or more. Here, NSI is an index indicating the solubility of protein. It is more preferred to use a protein material with an NSI of 85 or more, 90 or more, 95 or more, or 97 or more. A high NSI of a protein material indicates that the above-mentioned protein material has high dispersibility in water. Therefore, a high NSI can contribute to the dispersion stability of the oil-in-water emulsion composition used in the present embodiment. In addition, the crude protein content in the protein material can preferably be set to 30% by mass or more, and more preferably can be set to 35% by mass or more, 40% by mass or more, 45% by mass or more, 50% by mass or more, 55% by mass or more, 60% by mass or more, 65% by mass or more, or 70% by mass or more. A protein material with a higher crude protein content can perform the desired function with a smaller amount.

[0049] An example of such a protein material is MIRA-MAP 2.0 manufactured by Fuji Oil Co., Ltd.

[0050] The source of the protein material used in the above-mentioned preparation is not particularly limited. Proteins from vegetable, animal or microorganisms can be used. As examples of vegetable proteins, proteins from beans comprising soybeans, peas, mung beans, lupines, chickpeas, kidney beans, lentils and cowpeas, seeds comprising sesame, canola rapeseed seeds, coconut seeds and almond seeds, cereals comprising corn, buckwheat, wheat and rice, vegetables, fruits, algae and microalgae can be enumerated. As an example, when using protein from soybean as protein material, a protein material prepared by concentrating the protein contained in soybean raw materials such as defatted soybeans or whole soybeans can be used. Generally speaking, the examples of the above-mentioned protein materials conceptually include isolated soy protein, concentrated soy protein, powdered soy milk and protein materials obtained by various processing thereof.

[0051] Examples of animal proteins include egg proteins including egg white albumin, milk proteins including casein, whey, and lactalbumin, blood proteins including plasma, serum albumin, and decolorized hemoglobin, proteins from livestock meat, and proteins from fish and shellfish. Furthermore, proteins derived from microorganisms including yeast, mold, and bacteria can be used. Even proteins with poor solubility in water can be prepared into protein materials suitable for use in this embodiment through the treatment described below.

[0052] In one embodiment, a plant-based oil-in-water emulsion is produced. Therefore, in this embodiment, plant protein can be preferably used as the protein material.

[0053] (Denaturation and molecular weight adjustment treatment)

[0054] The protein material used in the oil-in-water emulsion manufactured in the present embodiment is obtained by combining a decomposition / denaturation process for decomposing and / or denaturing the protein and a molecular weight distribution adjustment process for adjusting the molecular weight distribution of the protein. As examples of the above-mentioned decomposition / denaturation process, enzyme treatment, pH adjustment process (such as acid treatment, alkali treatment), denaturant treatment, heat treatment, cooling treatment, high pressure treatment, organic solvent treatment, mineral addition process, supercritical treatment, ultrasonic treatment, electrolysis treatment and a combination of these processes can be enumerated. As examples of the above-mentioned molecular weight distribution adjustment process, filtration, gel filtration, chromatography, centrifugation, electrophoresis, dialysis and a combination of these processes can be enumerated. The order and number of decomposition / denaturation processes and molecular weight distribution adjustment processes are not particularly limited. Molecular weight distribution adjustment process can be carried out after decomposition / denaturation process. Alternatively, decomposition / denaturation process can be carried out after molecular weight distribution adjustment process. Furthermore, two processes can also be carried out simultaneously. In addition, for example, decomposition / denaturation process can be carried out between molecular weight distribution adjustment processes more than 2 times. Alternatively, molecular weight distribution adjustment process can be carried out between decomposition / denaturation process more than 2 times. Furthermore, the decomposition / denaturation treatment and the molecular weight distribution adjustment treatment may be performed multiple times in any order. It should be noted that when the desired molecular weight distribution is obtained by the decomposition / denaturation treatment, the molecular weight distribution adjustment treatment may not be performed. When these treatments are combined and performed multiple times, all the treatments may be performed continuously from the raw material. Alternatively, the above-mentioned treatments may be performed multiple times at intervals. For example, a commercially available product that has undergone a certain treatment as a raw material may be subjected to other treatments. It should be noted that as long as the above-mentioned characteristics are met, a specific protein material can be prepared by mixing a protein material that has undergone a molecular weight distribution adjustment treatment and a protein material that has not undergone a molecular weight distribution adjustment treatment. In this case, the ratio of the two (treated protein material: untreated protein material) can be appropriately adjusted within the range that meets the above-mentioned characteristics. Examples of the range of the ratio of the two include 1:99 to 99:1, 50:50 to 95:5, and 75:25 to 90:10. In a certain embodiment, the protein material used in the above-mentioned oil-in-water emulsion is composed of a protein material that has undergone decomposition / denaturation and molecular weight distribution adjustment treatment.

[0055] Those skilled in the art can appropriately set the conditions for the protein decomposition treatment and the conditions for the protein denaturation treatment, such as enzymes, pH, organic solvents, minerals, concentrations of components, temperature, pressure, output intensity, current and time. When using enzymes, examples of the enzymes used include proteases classified as metalloproteases, acid proteases, thiol proteases or serine proteases. The reaction can be carried out at a reaction temperature of 20 to 80°C, preferably 40 to 60°C. In the case of pH adjustment treatment, for example, the treatment can be carried out within a pH range having values ​​appropriately selected from pH 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5 and 12 as upper and lower limits. For example, the treatment can be carried out within a pH range of 2 to 12. The acid treatment can be a method of adding acid, or a method of performing a fermentation treatment such as lactic acid fermentation. Examples of added acids include inorganic acids such as hydrochloric acid and phosphoric acid, and organic acids such as acetic acid, lactic acid, citric acid, gluconic acid, phytic acid, sorbic acid, adipic acid, succinic acid, tartaric acid, fumaric acid, malic acid, and ascorbic acid. Acids may also be added using acid-containing foods and beverages, such as fruit juices including lemon juice, concentrated fruit juices, fermented milk, yogurt, and brewed vinegar. For alkaline treatment, sodium hydroxide or potassium hydroxide may be added as the base. For denaturant treatment, guanidine hydrochloride, urea, arginine, or PEG may be added as the denaturant. For heating or cooling treatment, examples of heating temperatures include 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, and 150°C. Treatment may be performed within a temperature range, for example, 60°C to 150°C, with upper and lower limits appropriately selected from these temperatures. Examples of cooling temperatures include -10°C, -15°C, -20°C, -25°C, -30°C, -35°C, -40°C, -45°C, -50°C, -55°C, -60°C, -65°C, -70°C, and -75°C. Treatment can be performed within a range with upper and lower limits appropriately selected from these temperatures, for example, from -10°C to -75°C. Examples of heating or cooling times include 5 seconds, 10 seconds, 30 seconds, 1 minute, 5 minutes, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 80 minutes, 90 minutes, 100 minutes, 120 minutes, 150 minutes, 180 minutes, and 200 minutes. Treatment can be performed within a range with upper and lower limits appropriately selected from these times, for example, from 5 seconds to 200 minutes.In the case of high-pressure treatment, examples of pressure conditions include 100 MPa, 200 MPa, 300 MPa, 400 MPa, 500 MPa, 600 MPa, 700 MPa, 800 MPa, 900 MPa and 1000 MPa. The treatment can be carried out in a range with a pressure appropriately selected from these pressures as the upper and lower limits, for example, 100 MPa to 1000 MPa. In the case of organic solvent treatment, examples of solvents used include alcohols and ketones, more specifically, ethanol and acetone. In the case of mineral addition treatment, examples of minerals used include divalent metal ions containing calcium and magnesium. In the case of supercritical treatment, for example, treatment can be carried out using supercritical carbon dioxide at a temperature of about 30°C or above and a pressure of about 7 MPa or above. In the case of ultrasonic treatment, for example, treatment can be carried out by irradiation at a frequency of 100 KHz to 2 MHz and an output of 100 to 1000 W. In the case of electrolysis, for example, the protein aqueous solution can be treated by applying a voltage of 100 to 1000 mV. In a specific embodiment, the treatment for decomposing and / or denaturing the protein is selected from treatment with a denaturant, heat treatment, and a combination thereof.

[0056] Those skilled in the art can appropriately set the processing conditions for adjusting the molecular weight distribution of proteins, such as the type of filter material, the support for gel filtration, the centrifugal speed, current, and time. Examples of filter materials include filter paper, filter cloth, diatomaceous earth, ceramics, glass, and membranes. Examples of supports for gel filtration include dextran and agarose. Examples of centrifugal conditions include 1000 to 3000 × g for 5 to 20 minutes.

[0057] The amount of the protein material used in this embodiment is preferably 0.01 to 5% by mass, more preferably 0.01 to 4% by mass, in the foamed vegetable milk. Further preferably, the amount can be 0.01 to 3% by mass, 0.01 to 2% by mass, 0.01 to 1% by mass, 0.03 to 3% by mass, 0.03 to 2% by mass, or 0.03 to 1% by mass.

[0058] (Crude protein content)

[0059] The crude protein content was determined by the Kjeldahl method. Specifically, the mass of nitrogen determined by the Kjeldahl method relative to the weight of the protein material is expressed as the crude protein content in the dry protein material in mass %. The nitrogen conversion factor was set to 6.25. The measured value was generally rounded to the nearest decimal place.

[0060] (NSI)

[0061] Add 60 ml of water to 3 g of sample. Stir the resulting mixture at 37°C with a propeller for 1 hour. Then, centrifuge the stirred mixture at 1400×g for 10 minutes. Collect the supernatant (I). Next, add 100 ml of water to the remaining precipitate again. After stirring at 37°C with a propeller for 1 hour again, centrifuge. Collect the supernatant (II). Mix liquid (I) and liquid (II). Add water to the mixed solution until the total amount of the mixed solution reaches 250 ml. Then, filter the mixed solution with filter paper (No. 5). Then, determine the nitrogen content in the filtrate by the Kjeldahl method. At the same time, determine the nitrogen content in the sample by the Kjeldahl method. The value expressing the ratio of the amount of nitrogen recovered from the filtrate (water-soluble nitrogen) to the total nitrogen content in the sample in mass % is defined as NSI. Basically, the measured value is obtained by rounding off the value to the second decimal place.

[0062] (TCA solubility rate)

[0063] An equal amount of 0.44 M trichloroacetic acid (TCA) is added to a 2% by mass aqueous solution of the protein material. Thus, a 0.22 M TCA solution is prepared. The proportion of soluble nitrogen is defined as the value determined by the Kjeldahl method. The measured value is generally rounded to the nearest decimal place.

[0064] (Viscosity (after heating))

[0065] The viscosity of the protein material is measured using a B-type viscometer (BM type, manufactured by Toki Sangyo Co., Ltd.). A protein material aqueous solution is prepared in such a way that the concentration of crude protein contained in the protein material is 20% by mass. A rotor is set in a measuring container filled with the prepared aqueous solution. Then, the sealed measuring container is heated at 80°C in a hot water bath for 30 minutes. Next, the viscosity of the aqueous solution in the measuring container is measured at 25°C at an appropriate rotation speed. The viscosity (unit: Pa·s) is calculated by multiplying the pointer value of the read viscometer by the conversion multiplier corresponding to the rotor No. and the rotation speed. The value obtained by the pointer value 1 minute after the start of the measurement is defined as the measured value. Basically, the above rotation speed is set to 60rpm. In the measurement of high-viscosity samples, the rotor No. is changed from 1 to 4. At the same time, the rotation speed is reduced to 6rpm. It should be noted that the upper limit viscosity of this measurement is 100,000mPa·s. Under the conditions of rotor No. 4 and a rotation speed of 6rpm, when the pointer value exceeds the measurement range, it is immediately determined that the viscosity after heating is 100,000mPa·s or more.

[0066] (grease)

[0067] Oils and fats can be added to the foaming plant milk of this embodiment. The added oils and fats can be any oils and fats as long as they are edible oils and fats. Examples of the added oils and fats include corn oil, soybean oil, sesame oil, rice bran oil, safflower oil, cottonseed oil, sunflower oil, rapeseed oil, coconut oil, palm oil, palm kernel oil, olive oil, peanut oil, almond oil, avocado oil, hazelnut oil, walnut oil and perilla seed oil, animal oils and fats including milk fat, beef tallow, lard, whale oil, fish oil and chicken oil, and oils and fats of microbial origin including yeast, mold and bacteria. If vegetable oils and fats are used, the physical properties of the oils and fats can be easily controlled, and by using vegetable ingredients as all the ingredients, the foaming plant milk can be prepared. Therefore, vegetable oils and fats are preferred. In addition, each of the above oils and fats can be used alone. Alternatively, a mixed oil of these oils and fats can be used. Alternatively, processed oils and fats obtained by processing these oils and fats, for example, by solidification, fractionation or transesterification can also be used.

[0068] The addition of fat tends to enhance the kokumi flavor of the foamed vegetable milk. Furthermore, the addition of fat tends to enhance the mouthfeel of the foamed vegetable milk. The amount of fat incorporated into the foamed vegetable milk can be preferably set to 0.01 to 6% by mass, more preferably 0.1 to 5% by mass, and even more preferably 0.5 to 5% by mass or 1 to 5% by mass.

[0069] In addition, the plant milk for foaming of this embodiment may contain, for example, fruit juice, pulp, vegetables, sugars, oils, dairy products, cereal flours, starches, cocoa mass, emulsifiers, minerals, vitamins, thickeners and stabilizers, acidulants or spices as appropriate.

[0070] (Method for producing plant milk for foaming)

[0071] An example of production of the vegetable milk for foaming according to this embodiment is shown.

[0072] Plant milk and a protein material having the following properties (A) and (B) are emulsified.

[0073] (A) After heating a 20% by mass aqueous solution of the protein material, calculated as crude protein contained in the protein material, at 80° C. for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25° C.

[0074] (B) The solubility rate of the above-mentioned protein material in 0.22 M TCA is 10% to 95%.

[0075] The obtained emulsion is homogenized using a homogenizer as needed. Then, the emulsion is sterilized as needed. In this way, the plant milk for foaming of this embodiment can be obtained.

[0076] In addition, for example, oils and fats, fruit juices, pulp, vegetables, sugars, fats and oils, dairy products, cereal flours, starches, cocoa mass, emulsifiers, minerals, vitamins, thickeners and stabilizers, acidulants, or flavorings can be used as appropriate.

[0077] The emulsification method is not particularly limited. For example, the vegetable milk and protein material can be emulsified using a homogenizer or a homogenizer. Furthermore, if necessary, the resulting emulsion can be homogenized using, for example, a homogenizer. The homogenization pressure of the homogenizer is not particularly limited as long as it is sufficient for emulsification.

[0078] (Sterilization)

[0079] The plant milk for foaming of this embodiment can be sterilized as needed. The sterilization method is not particularly limited. Examples of sterilization methods include injecting high-temperature and high-pressure water into the raw material liquid, injecting high-pressure steam into the raw material liquid, direct heating methods including Joule heating of the raw material liquid by passing electricity and heating by high frequency (microwave), and indirect heating methods including electromagnetic induction heating, electric furnace, direct fire, flowing sand bath and molten salt bath. Each of these sterilization methods can be used alone. Alternatively, several of these sterilization methods can be used in combination.

[0080] Alternatively, the sterilized foamed plant milk may be homogenized again using a homogenizer.

[0081] (Foaming)

[0082] For example, the foamable plant milk of this embodiment can be foamed using a steam engine or a bubbler. In this way, foamed plant milk can be obtained. In addition, the foamable plant milk is added together with nitrous oxide gas or carbon dioxide gas into a siphon for foam (espuma). Then, vibration is applied to the sealed siphon for foam by oscillation. Then, the content is squeezed out from the siphon for foam into a container. Foaming can also be implemented in this way. The foamed plant milk can be used in various beverages. Examples of such beverages include coffee, black tea and cocoa.

[0083] Taking coffee as an example, the foamable plant milk of this embodiment can be foamed using, for example, a frother. The foamed plant milk can then be added to coffee. This method allows for the preparation of a cappuccino-like beverage. This cappuccino-like beverage exhibits excellent foaming properties and foam stability, and exhibits a pleasant flavor.

[0084] Example

[0085] The present embodiment will be described below with reference to the following examples and comparative examples. It should be noted that, unless otherwise specified, "parts" in the examples and comparative examples refer to parts by mass. Similarly, "%" refers to mass %.

[0086] (Examples 1 to 5, Comparative Example 1)

[0087] Based on the formulation in Table 1, the raw materials were mixed with a homogenizer (manufactured by PRIMIX Co., Ltd.). The obtained mixture was homogenized with a homogenizer (manufactured by SPXFLOW Co., Ltd.) under the condition of 15 MPa. Thus, soy milk for foaming was obtained. It should be noted that as a protein material, MIRA-MAP 2.0 (manufactured by Fuji Oil Co., Ltd., crude protein content 79.3%, TCA solubility 61.8%, viscosity after heating 28 mPa·s, NSI 98.1) was used. As soy milk (plant milk), unadjusted soy milk (manufactured by KIKKOMAN Co., Ltd., protein content: 4.15%) was used. In addition, as a vegetable oil, edible rice bran oil (manufactured by Fuji Oil Co., Ltd.) was used.

[0088] 150 g of each soy milk for foaming was placed in a 400 ml milk frother (Stainless Steel Double Mesh Milk Foamer DIY Fancy Coffee Creamer). The milk frother was shaken up and down 20 times to obtain foamed soy milk.

[0089] (Evaluation of Foaming Properties and Foaming Stability)

[0090] The foamed soy milk was immediately poured into a 200 ml tall beaker. The height of the foam in the beaker was measured 1 minute and 10 minutes after the milk frother stopped vibrating. The foam height after 1 minute (first foam height) was defined as an indicator of foamability. Furthermore, foam stability was evaluated by dividing the foam height after 10 minutes (second foam height) by the first foam height to calculate the percentage (%).

[0091] The foamed soymilk is judged to be acceptable if the foamability index (first foam height) is 44 mm or greater and the foam stability is 65% or greater. The foamability is preferably 45 mm or greater, more preferably 47 mm or greater. Furthermore, the foam stability is preferably 66% or greater, more preferably 67% or greater.

[0092] (Table 1)

[0093]

[0094] As shown in Table 1, it was confirmed that the soymilk for foaming according to the present embodiment prepared using the protein material had good foaming properties and foaming stability.

[0095] (Examples 6 to 9) Study on the amount of fat added

[0096] Soy milk for foaming was prepared in the same manner as in Example 1 except that the amount of vegetable oil added was varied within the range of 0.03 to 5% according to the formulation shown in Table 2. The foamed soy milk obtained from the prepared soy milk for foaming was evaluated. The results are shown in Table 2.

[0097] (Table 2)

[0098] Cooperate(%) Example 6 Example 7 Example 8 Example 9 soy milk 70 70 70 70 vegetable oils and fats 0.3 1 3 5 granulated sugar 1.3 1.3 1.3 1.3 water 28.35 27.65 25.65 23.65 Protein materials 0.05 0.05 0.05 0.05 total 100 100 100 100 First foam height (m) 47 48 63 70 Second foam height (mm) 35 35 46 48 Foaming stability (%) 74.5 72.9 73.0 68.6

[0099] As shown in Table 2, even when the amount of oil added was set to 5%, measurement results showing good foaming properties and foam stability were obtained.

[0100] (Examples 10-13, Comparative Examples 2-3) Study on Soymilk Ratio

[0101] Previous studies have confirmed the foaming properties and foam stability of soy milk foaming solutions containing 70% soy milk. The authors investigated the impact of reducing the soy milk content on foaming properties and foam stability. Therefore, the soy milk content was set within a range of 5% to 90%.

[0102] (Table 3)

[0103]

[0104] As shown in Table 3, it was confirmed that foaming properties and foaming stability decreased when the soy milk ratio was 10% or less. It was confirmed that foamed soy milk with good foaming properties and foaming stability was obtained when the soy milk ratio was at least 25%.

[0105] (Examples 14-15) Research on other plant milks

[0106] The foaming properties and foaming stability of plant milks containing almond milk or oat milk, as plant milks other than soy milk, were examined. Plant milks for foaming were prepared using the same method as in Example 1, except that almond milk or oat milk was used instead of soy milk, based on the formulations shown in Table 4. The foaming properties and foaming stability of each foamed plant milk were evaluated using the same method as in Example 1.

[0107] As almond milk, concentrated almond milk without sugar (produced by Tsukuba Milk Industry Co., Ltd., protein content: 3.6%) was used. The oat milk used was prepared by the following method. First, 700 parts of water and 0.1 part of α-amylase were added to 100 parts of oat flour. The resulting mixture was enzymatically treated at 60°C for 30 minutes. Then, solid-liquid separation by centrifugation and sterilization were performed to obtain oat milk (protein content: 0.7%).

[0108] (Table 4)

[0109]

[0110] As shown in Table 4, it was confirmed that foamed vegetable milk having good foaming properties and foaming stability could be prepared even when almond milk or oat milk was used.

[0111] The foregoing detailed description has been presented for purposes of illustration and description. Many modifications and variations are possible in light of the above teachings. It is not intended to be exhaustive or to limit the subject matter described herein to the precise forms disclosed. Although the subject matter has been described in language specific to structural features and / or methodological acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the appended claims.

Claims

1. A plant milk for foaming, comprising plant milk and a protein material having the following properties (A) and (B), (A) after heating an aqueous solution of the protein material containing 20% ​​by mass, calculated as crude protein contained in the protein material, at 80° C. for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25° C., (B) The solubility rate of the protein material in 0.22 M TCA is 10% to 95%.

2. The plant milk for foaming according to claim 1, wherein In the property (A), the viscosity is 10,000 mPa·s or less.

3. The plant milk for foaming according to claim 1, wherein In the property (B), the 0.22 M TCA solubility rate of the protein material is 30% to 95%.

4. The plant milk for foaming according to claim 1, wherein In the property (A), the viscosity is 10,000 mPa·s or less, and in the property (B), the 0.22 M TCA solubility rate of the protein material is 30% to 95%. 5 . A plant milk beverage covered with foamed plant milk prepared by foaming the plant milk for foaming according to claim 1 .

6. A method for producing a foaming plant milk, comprising the steps of emulsifying the plant milk and a raw material containing a protein material having the following properties (A) and (B): (A) after heating an aqueous solution of the protein material containing 20% ​​by mass, calculated as crude protein contained in the protein material, at 80° C. for 30 minutes, the aqueous solution has a viscosity of less than 100,000 mPa·s at 25° C., (B) The solubility rate of the protein material in 0.22 M TCA is 10% to 95%.

7. A method for producing foamed vegetable milk, comprising the step of foaming the foaming vegetable milk according to any one of claims 1 to 4.

8. A method for foaming plant milk, comprising the step of foaming the plant milk according to any one of claims 1 to 4.

Images