Mouthfeel improving agent for liquid composition containing vegetable protein

Abstract

The purpose of the present invention is to provide a processing technique for obtaining a vegetable protein-containing liquid composition having a high content of vegetable protein material of 6% by weight or more and improved roughness. In the present invention, when a liquid composition containing a vegetable protein, which contains 6 wt% or more of a vegetable protein material, is treated with a protein deamidase, the texture of the liquid composition containing a vegetable protein can be improved.

Description

Technical Field

[0001] The present invention relates to a mouthfeel improving agent for a liquid composition containing vegetable protein, and more specifically, to a processing technology for a liquid composition containing vegetable protein having a high content of vegetable protein material of 6% by weight or more and improved roughness. Background Art

[0002] Nutritious plant milk is gaining popularity as an alternative to animal milk due to various reasons, including the recent health craze, measures to combat allergies, and religious reasons.

[0003] Unlike animal milk, which is generally a secretion, plant milk is prepared by dispersing crushed plant tissue in water. Therefore, as a basic characteristic of an animal milk substitute, it is required to have a smooth taste. In the process of improving plant milk, it is also expected to consider such basic characteristics. For example, Patent Document 1 states: In order to improve soy milk to contain a high concentration of soy isoflavones, soybean hypocotyls or processed products of soybean hypocotyls with a total amount of 1050 to 2800 mg / 100 g of soy isoflavones are ground in soy milk to contain 4 to 10% by weight, and wet micronization is performed by high-pressure homogenization without separating the dregs, thereby making it possible to produce smooth soy milk containing a high concentration of soy isoflavones. Prior art literature

[0004] Patent Document 1: International Publication No. 2005 / 087019 Summary of the invention

[0005] Technical problem to be solved by the invention Plant milk has less protein than animal milk, so there is a problem in protein intake efficiency. When the inventors want to prepare plant milk with a high protein content, they face the following problem: if the vegetable protein material is a high content of 6% by weight or more, the mouthfeel will be significantly deteriorated to the extent of producing a rough feeling.

[0006] Therefore, an object of the present invention is to provide a processing technology for obtaining a liquid composition containing vegetable protein having a high content of vegetable protein material of 6% by weight or more and improved roughness.

[0007] Technical solutions for solving technical problems The present inventors have found that the roughness of a liquid composition containing vegetable protein having a vegetable protein material content of 6% by weight or more can be improved by treating the liquid composition with a protein deamidase. The present invention was completed through further research based on these findings.

[0008] That is, the present invention provides the following inventions.

[0009] Item 1. A mouthfeel improver, characterized in that the mouthfeel improver comprises a protein deamidase and is used to improve the mouthfeel of a liquid composition containing a vegetable protein material in an amount of 6% by weight or more.

[0010] Item 2. The texture improving agent according to Item 1, wherein the vegetable protein content in the vegetable protein-containing liquid composition is 5% by weight or more.

[0011] Item 3. The texture improver according to Item 1 or 2, wherein the plant protein is a plant protein selected from soybeans, peas, lentils, chickpeas, broad beans, mung beans, lupines, wheat, barley, oats, sorghum, corn, peanuts and chia seeds.

[0012] Item 4. The texture improving agent according to any one of Items 1 to 3, wherein the plant protein is a plant protein selected from lupin, wheat, oats, corn, and chia seeds.

[0013] Item 5. A method for producing a liquid composition containing vegetable protein having an improved taste, characterized in that the method comprises a step of allowing a protein deamidase to act on the liquid composition containing vegetable protein having a vegetable protein material content of 6% by weight or more.

[0014] Effects of the Invention According to the present invention, there is provided a technology for processing a liquid composition containing vegetable protein, which has a high content of vegetable protein material of 6% by weight or more and has an improved rough texture. DETAILED DESCRIPTION

[0015] 1. Taste improver for liquid composition containing vegetable protein The mouthfeel improver of the present invention is characterized by comprising a protein deamidase and being used for improving the mouthfeel of a liquid composition containing vegetable protein and containing 6% by weight or more of a vegetable protein material.

[0016] 1-1. Application The mouthfeel improver of the present invention is used to improve the mouthfeel of a liquid composition containing vegetable protein in which the content of vegetable protein material is 6% by weight or more. In the present invention, mouthfeel refers to the feeling of roughness on the tongue. Improving mouthfeel means reducing the degree of roughness felt on the tongue, and preferably means imparting smoothness.

[0017] It should be noted that the improvement in mouthfeel can be confirmed in the following sensory manner: the tongue feels that when the mouth contains a liquid composition containing vegetable protein treated with the mouthfeel improver of the present invention, the degree of roughness is reduced compared to the case where the mouth contains a liquid composition containing vegetable protein not treated with the mouthfeel improver of the present invention. In addition, the improvement in mouthfeel can also be confirmed in the following manner: using an apparatus using an artificial tongue and artificial saliva to simulate the oral cavity, the friction coefficient of the liquid composition containing vegetable protein treated with the mouthfeel improver of the present invention is measured, and the friction coefficient obtained is reduced compared to the case of the liquid composition containing vegetable protein not treated with the mouthfeel improver of the present invention.

[0018] The liquid composition containing vegetable protein as the application object of the mouthfeel improver of the present invention is not particularly limited as long as it is a liquid containing vegetable protein in water. Specific examples of the liquid composition containing vegetable protein include: (i) a liquid obtained by dispersing a dry powder of a food material containing vegetable protein (specifically, a plant organ of a plant source of vegetable protein, and a material in which the content of the protein is increased by removing at least a part of the components other than protein from the above-mentioned plant organ. The same applies below) in water; (ii) a liquid obtained by crushing and dispersing a food material containing vegetable protein in water, and removing insoluble matter such as skin derived from the food material by any means such as centrifugation, filtration, filter bag, sieving, etc. as needed; (iii) a liquid obtained by removing components other than vegetable protein from the liquid of the above (i) or (ii) to increase the content of vegetable protein; (iv) a liquid obtained by mixing a dry powder prepared from any of the above liquids (i) to (iii) with water, etc. Preferred examples of the liquid composition containing vegetable protein include vegetable milk.

[0019] There are no particular restrictions on food materials containing vegetable proteins. Specific examples of food materials containing vegetable proteins include beans such as soybeans, peas, lentils, chickpeas, black beans, broad beans, mung beans, lupines, and kidney beans; cereals such as wheat, barley, oats, sorghum, rice, rye, buckwheat, barnyard grass, millet, teff, corn, and potatoes; nuts such as almonds, coconuts, peanuts, cashews, hazelnuts, pecans, macadamia nuts, pistachios, walnuts, Brazil nuts, pili nuts, chestnuts, sesame seeds, and pine nuts; seeds such as chia seeds, chia seeds (Japanese: キア), amaranth seeds, canary seeds, and flax seeds. In the liquid composition containing vegetable proteins, the above-mentioned vegetable proteins can be contained alone or in a variety of combinations. Among these vegetable proteins, from the viewpoint of further improving the effect of improving the taste, soybeans, peas, lentils, chickpeas, broad beans, mung beans, lupins, wheat, barley, oats, sorghum, corn, peanuts and chia seeds are preferred, and lupins, wheat, oats, corn and chia seeds are more preferred. It should be noted that the vegetable protein contained in the liquids of (i) to (iv) above may be in any of the following forms: protein contained in plant organs (natural protein); protein partially decomposed chemically by acid, alkali or the like; protein partially decomposed by enzymes by the action of proteases or the like; chemically modified proteins obtained by various reagents, etc.

[0020] It should be noted that in the present invention, the "content of plant protein material" in the liquid composition containing plant protein refers to the proportion of the dry weight of the components constituting the above-mentioned plant organs contained in the liquid composition containing plant protein. For example, in the case where the liquid composition containing plant protein is a liquid composed only of components derived from plant organs and water, such as the liquids (i) to (iv) above, the "content of plant protein material" refers to the proportion of the dry weight of the liquid. In addition, for example, in the case where the liquid composition containing plant protein is a liquid containing the liquids (i) to (iv) above and additives, the "content of plant protein material" refers to the proportion of the dry weight of the portion after removing the additive from the liquid.

[0021] The content of the vegetable protein material in the liquid composition containing vegetable protein to which the mouthfeel improver of the present invention is applied is 6% by weight or more. If the content of the vegetable protein material in the liquid composition containing vegetable protein reaches a high content of 6% by weight or more, the mouthfeel will be significantly reduced to the extent that a rough feeling is generated, but the mouthfeel improver of the present invention can effectively improve the rough feeling even if the vegetable protein material is a liquid composition containing vegetable protein with a high content. Therefore, as a preferred example of the content of the vegetable protein material in the liquid composition containing vegetable protein, preferably 7% by weight or more, more preferably 8% by weight or more, and further preferably 9% by weight or more.

[0022] The upper limit of the content of the vegetable protein material in the liquid composition containing vegetable protein is not particularly limited, and for example, 20% by weight or less can be cited. From the viewpoint of further improving the roughness improvement effect, the upper limit of the content of the vegetable protein material in the liquid composition containing vegetable protein is preferably 17% by weight or less, more preferably 13% by weight or less, and further preferably 11% by weight or less.

[0023] In addition, the vegetable protein content in the liquid composition containing vegetable protein is determined according to the type of food material serving as the vegetable protein source and the content of the vegetable protein material, but for example, it can be 1% by weight or more, preferably 5% by weight or more, more preferably 6% by weight or more, further preferably 6.5% by weight or more, even more preferably 7% by weight or more, or 7.5% by weight or more, and further preferably 8% by weight or more; as its upper limit, for example, it can be 20% by weight or less, preferably 17% by weight or less, more preferably 13% by weight or less, further preferably 11% by weight or less, and further preferably 10% by weight or less.

[0024] 1-2. Protein deamidase The texture improver of the present invention contains a protein deamidase as an active ingredient. The texture improver of the present invention can improve the roughness of the obtained liquid composition containing vegetable protein by the action of the protein deamidase on the liquid composition containing vegetable protein at a predetermined concentration.

[0025] The protein deamidase used in the present invention is not particularly limited in type and origin, as long as it is an enzyme that can decompose the amide-containing side chain of the protein without cleavage of peptide bonds and cross-linking of proteins. In addition, as long as the above-mentioned action is the main activity, it may further have the action of decomposing the amide-containing side chain of the protein accompanied by cleavage of peptide bonds and cross-linking of proteins.

[0026] Examples of protein deaminases include: enzymes that deamidate glutamine residues in proteins and convert them into glutamate (e.g., protein glutaminase); enzymes that deamidate asparagine residues in proteins and convert them into aspartic acid (e.g., protein asparaginase); and enzymes that deiminate the guanidine group of the arginine residue at the C-terminus of proteins (e.g., protein arginine deiminase). Among them, protein glutaminase is preferred from the viewpoint of further improving the effect of improving the taste.

[0027] As a more specific example of protein deamidase, there can be mentioned: protein deamidase derived from Chryseobacterium, Flavobacterium, Empedobacter, Sphingobacterium, Aureobacterium, Myroides, Luteimicrobium, Agromyces, Microbacterium, or Leifsonia. These protein deamidase are well known, for example, JP2000-50887A, JP2001-218590A, WO2006 / 075772A1, WO2015 / 133590, etc. These protein deamidase can be used alone or in combination.

[0028] Among these protein deaminases, from the viewpoint of further improving the taste-improving effect, preferably, a protein deamidase derived from the genus Chryseobacterium is used, more preferably, a protein glutaminase derived from the genus Chryseobacterium is used, further preferably, a protein glutaminase derived from the species Chryseobacterium proteolyticum is used, and even more preferably, a protein glutaminase derived from Chryseobacterium proteolyticum 9670 is used.

[0029] Protein deamidase can be prepared from the culture solution of the microorganism as the source of the above-mentioned protein deamidase. As a specific preparation method, a method for recovering protein deamidase from the culture solution or bacterial cell of the above-mentioned microorganism can be cited. For example, in the case of using a protein deamidase secretory microorganism, the bacterial cell can be recovered from the culture solution by filtering, centrifugation, etc. in advance as needed, and then the enzyme is separated and / or purified. In addition, in the case of using a protein deamidase non-secreting microorganism, the bacterial cell can be recovered from the culture solution in advance as needed, and then the bacterial cell is broken by pressure treatment, ultrasonic treatment, lysozyme treatment, etc. to expose the enzyme, and then the enzyme is separated and / or purified. As a separation and / or purification method of the enzyme, a known protein separation and / or purification method can be used without particular limitation, for example, centrifugation, UF concentration method, salting-out method, various chromatography methods using ion exchange resins, etc. can be cited. The enzyme obtained by separation and / or purification can be powdered by drying methods such as freeze drying and reduced pressure drying, and in addition, it can also be powdered using appropriate excipients and / or drying aids in the drying method. Alternatively, the isolated and / or purified enzyme can be liquefied by adding appropriate additives and sterilizing by filtration.

[0030] The amount of the protein deamidase contained in the texture improving agent of the present invention is not particularly limited as long as the effect of the protein deamidase can be effectively obtained when the texture improving agent of the present invention is used, and examples thereof include 0.1 U / g to 5000 U / g.

[0031] It should be noted that regarding the activity of protein deamidase, benzyloxycarbonyl-L-glutaminoglycine (Z-Gln-Gly) is used as a substrate and 1 μ The amount of enzyme per mol of ammonia is taken as 1 unit (1U).

[0032] 1-3. Other ingredients The mouthfeel improving agent of the present invention may or may not contain other components in addition to the above-mentioned protein deamidase, as long as the effects of the present invention are not affected. Examples of other components include enzymes other than protein deamidase, additives, and the like.

[0033] As other enzymes, one or more enzymes can be appropriately selected based on the type and composition of the liquid composition containing vegetable protein to which the texture improving agent of the present invention is applied, and in accordance with a desired reaction other than the reaction using the protein deamidase.

[0034] As additives, it is possible to appropriately select according to the desired preparation form. The preparation form of the mouthfeel improver of the present invention is not particularly limited, and can be any of a solid preparation and a liquid preparation. Therefore, as additives, for example, excipients, buffers, suspending agents, stabilizers, preservatives, preservatives, water, pH adjusters, etc. can be cited. These additives can be included alone or in a variety of combinations.

[0035] 2. Method for producing a liquid composition containing vegetable protein with improved taste The present invention also provides a method for producing a liquid composition containing vegetable protein having improved taste, the method comprising the step of allowing a protein deamidase to act on the liquid composition containing vegetable protein having a vegetable protein material content of 6% by weight or more.

[0036] 2-1. Step of allowing protein deamidase to act The type of the liquid composition containing vegetable protein and the type of the protein deamidase in the step of allowing the protein deamidase to act are as described in the above section "1. Taste improving agent for liquid composition containing vegetable protein".

[0037] In addition, regarding the amount of protein deamidase used, as the amount of protein deamidase used per 1g of vegetable protein material (dry weight) contained in the liquid composition containing vegetable protein, for example, 0.25U or more can be cited, preferably 0.5U or more. From the viewpoint of further improving the effect of improving the taste, as the amount of protein deamidase used per 1g of vegetable protein material (dry weight) contained in the liquid composition containing vegetable protein, preferably 1U or more, more preferably 2U or more, further preferably 3U or more, and even more preferably 4U or more, or 4.5U or more. As the upper limit of the range of the amount of protein deamidase used per 1g of vegetable protein material (dry weight) contained in the liquid composition containing vegetable protein, there is no particular limitation, but for example, 500U or less, 250U or less, 100U or less, 75U or less, 50U or less, 25U or less, 10U or less, or 7.5U or less can be cited.

[0038] In addition, regarding the amount of protein deamidase used, as the amount of protein deamidase used per 1g of vegetable protein contained in the liquid composition containing vegetable protein, for example, 0.25U or more can be cited, preferably 0.5U or more. From the viewpoint of further improving the effect of improving the taste, as the amount of protein deamidase used per 1g of vegetable protein contained in the liquid composition containing vegetable protein, 1U or more is preferred, 2U or more is more preferred, 3U or more is further preferred, 4U or more, or 4.5U or more is further preferred. As the upper limit of the range of the amount of protein deamidase used per 1g of vegetable protein contained in the liquid composition containing vegetable protein, there is no particular limitation, but for example, 500U or less, 250U or less, 100U or less, 75U or less, 50U or less, 25U or less, or 20U or less can be cited.

[0039] In the step of allowing the protein deamidase to act, a liquid composition containing vegetable protein is mixed with the protein deamidase, and the protein deamidase is allowed to act on the protein in the liquid composition containing vegetable protein, thereby performing a reaction to improve the taste. Regarding the reaction conditions, those skilled in the art can consider the temperature and pH characteristics of the protein deamidase used, and appropriately set the reaction temperature and pH of the protein deamidase acting on the protein in the liquid composition containing vegetable protein, and the reaction time for allowing the reaction to proceed to a sufficient degree to improve the taste, etc. through preliminary tests, etc.

[0040] The reaction temperature can be determined according to the optimum temperature of the protein deamidase used, and is, for example, 10° C. to 80° C., preferably 20° C. to 70° C., more preferably 40° C. to 60° C., and further preferably 45° C. to 55° C. The pH can be determined according to the optimum pH of the protein deamidase used, and the pH at 25° C. is, for example, 5 to 10, preferably 5 to 8, and more preferably 6 to 8. The reaction time can be determined according to the reaction scale, and is, for example, 1 hour to 48 hours, preferably 1 hour to 24 hours, and more preferably 8 hours to 20 hours or 10 hours to 18 hours.

[0041] 2-2. Other processes The production method of the present invention may include other steps in addition to the above-mentioned step of allowing the protein deamidase to act.

[0042] Specific examples of other steps include a protein deamidase inactivation step, a cooling step, and a filtration step.

[0043] 2-3. Liquid composition containing vegetable protein with improved taste The liquid composition containing vegetable protein with improved taste obtained by the production method of the present invention is endowed with a taste that is improved compared to the liquid composition containing vegetable protein that has not been treated with the taste improver of the present invention. The obtained liquid composition containing vegetable protein with improved taste can be used directly or through appropriate cooking as, for example, a vegetable milk substitute, a cream substitute, a yogurt substitute, a cheese substitute, an ice cream substitute, etc. Example

[0044] The present invention will be specifically described below with reference to examples, but the present invention should not be construed as being limited to the following examples.

[0045] [Enzymes used] As the protein deamidase, PG, which is a protein glutaminase derived from Chryseobacterium proteolyticum (manufactured by Amano Enzyme Co., Ltd.), was used.

[0046] [Enzyme activity determination method] 0.1 mL of a sample solution containing protein deamidase was added to 1 mL of 0.2 M phosphate buffer (pH 6.5) containing 30 mM Z-Gln-Gly, and the mixture was allowed to stand at 37°C for 10 minutes, followed by the addition of 1 mL of 0.4 M TCA solution to stop the reaction. As a blank control, 1 mL of 0.4 M TCA solution was added to 1 mL of 0.2 M phosphate buffer (pH 6.5) containing 30 mM Z-Gln-Gly, and 0.1 mL of a sample solution containing protein deamidase was further added, followed by the addition of 1 mL of the solution, and the mixture was allowed to stand at 37°C for 10 minutes.

[0047] The amount of ammonia generated in the reaction solution was measured using Ammonia-test Wako (Fujifilm Wako Pure Chemical Industries, Ltd.). A calibration curve showing the relationship between ammonia concentration and absorbance (630 nm) was prepared using an ammonia standard solution (ammonium chloride), and the ammonia concentration in the reaction solution was determined using this calibration curve.

[0048] Will be able to generate 1 in 1 minute μ The activity of protein deamidase was calculated by the following formula, with the amount of enzyme per mol of ammonia as 1 unit (1U). In the formula, the amount of reaction solution is 2.1, the amount of enzyme solution is 0.1, and Df is the dilution ratio of the enzyme solution. In addition, 17.03 is the molecular weight of ammonia.

[0049] [Number 1] Protein deamidase activity (U / mL) = ammonia concentration in reaction solution (mg / L) × (1 / 17.03) × (reaction solution volume / enzyme solution volume) × (1 / 10) × Df [Food materials as a source of plant protein (hereinafter referred to as "plant protein materials")] Use the plant-based protein materials (all powders) shown in the table below.

[0050] [Table 1]

[0051] [Test example] (1) Test operation Each of the vegetable protein materials in Table 1 was mixed with a phosphate buffer solution at pH 7.0 (25° C.) so that the vegetable protein materials had the contents shown in Tables 2 to 5, thereby preparing a liquid composition containing vegetable protein. PG was added to the liquid composition containing vegetable protein in an amount of 5 U per 1 g of the vegetable protein material, and the mixture was incubated at 50° C. overnight to obtain a treated liquid composition containing vegetable protein (“with” PG). In addition, the same operation was performed except that PG was not added to obtain a treated liquid composition containing vegetable protein (“without” PG).

[0052] (2) Evaluation (2-1) Taste evaluation Two trained panelists put the treated plant protein-containing liquid composition obtained in (1) above into their mouths, checked the mouth feel (tongue feel), and classified the composition based on the following criteria. The results are shown in Tables 2 to 5.

[0053] ××: Strongly felt roughness ×: Feel roughness △: Roughness almost disappeared ○: Feel smoothness ◎: Strong sense of smoothness (2-2) Evaluation of protein solubility The treated liquid composition containing vegetable protein obtained in (1) above was centrifuged at 15,000 g for 5 minutes. The supernatant was recovered and the protein concentration was quantified using Bradford reagent produced by BIO-RAD. The relative value of the protein concentration of the treated liquid composition containing vegetable protein (without PG) was derived when the protein concentration of the treated liquid composition containing vegetable protein (without PG) was set to 1. The results are shown in Tables 2 to 5.

[0054] [Table 2]

[0055] [Table 3]

[0056] [Table 4]

[0057] [Table 5]

[0058] As shown in Reference Examples 1 and 3, the problem of roughness does not occur in the liquid composition containing vegetable protein with a low content of vegetable protein material, but as shown in Comparative Examples 1 to 16, the problem of significant roughness occurs in the liquid composition containing vegetable protein with a high content of vegetable protein material. As shown in Reference Examples 2 and 4, when the liquid composition containing vegetable protein with a low content of vegetable protein material is treated with PG, the mouthfeel is slightly improved or the mouthfeel does not change, but as shown in Examples 1 to 16, when the liquid composition containing vegetable protein with a high content of vegetable protein material is treated with PG, the mouthfeel is significantly improved. Among them, when the vegetable protein material is oats, lupines, wheat, corn or chia seeds, the effect of improving the mouthfeel is particularly significant.

Claims

1. A mouthfeel improver, characterized in that The mouthfeel improving agent comprises a protein deamidase and is used to improve the mouthfeel of a liquid composition containing vegetable protein and containing 6% by weight or more of a vegetable protein material.

2. The mouthfeel improving agent according to claim 1, wherein The vegetable protein content in the vegetable protein-containing liquid composition is 5% by weight or more.

3. The mouthfeel improving agent according to claim 1, wherein The vegetable protein is a plant protein selected from soybeans, peas, lentils, chickpeas, broad beans, mung beans, lupins, wheat, barley, oats, sorghum, corn, peanuts and chia seeds.

4. The mouthfeel improving agent according to claim 1, wherein The vegetable protein is a plant protein selected from lupin, wheat, oats, corn and chia seeds.

5. A method for producing a liquid composition containing vegetable protein with improved taste, characterized in that: The production method includes the step of allowing a protein deamidase to act on a liquid composition containing a vegetable protein material in an amount of 6% by weight or more.

Images