Method for producing protein beverage with reduced off-flavor

Abstract

To provide a protein beverage in which the generation of off-flavor, which is unique to protein, is suppressed.SOLUTION: At the time of producing protein beverage, by mixing, as a medium-chain fatty acid, an amount corresponding to 0.1 to 5 wt.% for the protein beverage in a state where the medium-chain fatty acid constitutes triacylglycerol, and subjecting to heat-sterilization, it becomes possible to obtain a protein beverage in which the generation of off-flavor is reduced and having a good flavor.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a protein beverage having reduced off-flavors. [Background technology]

[0002] In recent years, people have become increasingly health conscious, and the market for health foods has expanded significantly. Among them, protein has been attracting particular attention from the perspective of its nutritional components and physiological effects. Among these, soy protein, which is sourced from soybeans, is expected to be a source of protein, have anti-cholesterol effects, and have fat burning effects. Soy protein ingredients such as isolated soy protein have come to be used as ingredients in the development of health foods, including powdered drinks and baked goods that tout these effects. Other proteins that are also used include those sourced from peas, milk proteins sourced from milk, and whey proteins.

[0003] These protein ingredients, especially those derived from soybeans, are often used in high concentrations in the nutrition and health markets and the high-nutrition liquid food markets. However, high concentrations can cause problems such as the generation of the so-called soybean odor, which is made up of unpleasant odor components such as aldehydes, ketones, and alcohols that are naturally present in soybeans or that are generated during processing, and a strong bitter and astringent aftertaste, leading to a growing demand for further improvements in flavor. Even with pea and milk proteins, there is a demand from the market for improvement due to the off-flavor characteristic of isolated proteins. Among these, a method for reducing the soybean odor has been devised, as in Patent Document 1, but further improvement of flavor is required.

[0004] In addition, soy protein is prone to flavor deterioration during long-term storage at room temperature, and although many markets have called for improvements, they are still not sufficient. In addition, Patent Document 2 proposes a method of using supercritical carbon dioxide to produce soy protein products with reduced unpleasant odors, but all of these methods utilize special substances such as cultures of specific lactic acid bacteria or supercritical carbon dioxide. On the other hand, there were inventions that combined MCT (medium-chain fatty acid oils) with protein other than those that were expected to improve flavor. For example, there is an invention of a gelled emulsified food containing 10-40% by mass of fats and oils, 0-5% by mass of carbohydrates, and 1-10% by mass of protein, and containing 7-23% by mass of medium-chain fatty acids (Patent Document 3). However, this invention aims to suppress postprandial discomfort in a gelled emulsified food that is high in medium-chain fatty acids and low in carbohydrates, and is high in calories and low in carbohydrates. Since the objective of this invention is different, the amount of MCT added is extremely large, and this invention is fundamentally different from the present invention, which aims to improve flavor. There are other inventions of protein materials using MCT, such as Patent Document 4, but these are expected to provide basic nutritional functions, and the amount of MCT added, which has physiologically advantageous functions, is necessarily large, and there was no suggestion at all of the present invention that improves flavor, and that the problem can be solved by adding MCT at a specific timing in the process. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-319046 A [Patent Document 2] Special Publication No. 2008-543343 [Patent Document 3] JP 2016-021889 A [Patent Document 4] JP 2012-197293 A Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention aims to provide a protein drink in which the generation of off-flavors specific to proteins is suppressed, by a relatively simple method. [Means for solving the problem]

[0007] As a result of intensive research into the above-mentioned problems, the inventors discovered that by mixing medium-chain fatty acids equivalent to 0.1 to 5% by weight with a protein beverage in a state in which triacylglycerol is formed, and then heat sterilizing the beverage, the occurrence of off-flavors can be reduced and a beverage with a good flavor can be obtained, which led to the completion of the present invention.

[0008] That is, the present invention provides: (1) A method for producing a protein beverage containing protein, comprising mixing medium-chain fatty acids in an amount of 0.1 to 5% by weight with the protein beverage and sterilizing the mixture by heating, wherein the medium-chain fatty acids are used in a state in which they form triacylglycerol. (2) A method for producing a protein drink according to (1), comprising mixing 0.05 to 1.5% by weight of ethanol with the protein drink and sterilizing the mixture by heating. (3) The method for producing a protein beverage according to (1) or (2), wherein the ethanol is a distilled alcoholic beverage. (4) A method for producing a protein drink according to any one of (1) to (3), which contains 1 to 12 weight % of vegetable-derived protein. (5) A method for producing a protein drink according to any one of (1) to (4), comprising heat sterilizing the drink at 80°C to 160°C for 2 seconds to 60 minutes. (6) A method for producing a protein drink according to any one of (1) to (5), wherein the heat treatment comprises a direct heating step and a deaeration step. Effect of the Invention

[0009] According to the present invention, a protein beverage in which the development of off-flavors is suppressed can be provided in a relatively simple manner. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention will be described in detail below.

[0011] (protein drink) Protein drinks are made by dissolving or dispersing protein in a water phase. Although it is referred to as a beverage here, and its main use is as a beverage, there is no limitation on its use as long as it is a protein solution, and it may then be used as a raw material for some protein-containing food. In the present invention, a protein material is a raw material that contains protein as a main component and is used in the production of various foods, beverages, and other processed products. This protein material is prepared by further processing a raw material containing protein (protein raw material).

[0012] (Protein raw material) The origin of the protein raw material is not particularly limited as long as it contains protein, but it can be roughly divided into vegetable protein materials and animal protein materials. In this specification, a vegetable protein material is one whose main component is vegetable protein, and an animal protein material is one whose main component is animal protein, and both are food materials used as ingredients in various processed foods and beverages. Examples of the origin of the vegetable protein material include beans such as soybeans, peas, mung beans, lupine beans, chickpeas, kidney beans, lentil beans, cowpeas, etc., seeds such as sesame seeds, canola seeds, coconut seeds, almond seeds, etc., grains such as corn, buckwheat, wheat, rice, etc., vegetables, fruits, etc. As an example, in the case of a protein material derived from soybeans, it is prepared by further concentrating and processing the protein from soybean raw materials such as defatted soybeans and whole soybeans, and generally conceptually includes isolated soybean protein, concentrated soybean protein, powdered soybean milk, or various processed products thereof. Examples of the origin of the animal protein material include milk protein and gelatin, and examples of the milk protein material include whey protein, casein or a salt thereof, whole milk powder, skim milk powder, TMP, MPC, etc. More preferably, it is more preferable to use a vegetable protein material than an animal protein material, which is a concern these days for its environmental impact. Also, plant-derived materials are more likely to have an off-flavor in the human palate than animal-derived materials, and the off-flavor reduction technology of the present application can be used more preferably even for vegetable protein materials, which have been difficult to utilize. Also, soybean-derived protein materials are most suitable in terms of the amount and cost of resources, as well as the inherent strength of the off-flavor.

[0013] (Protein content in protein drinks) In the present invention, the protein content in the protein drink is preferably 12% by weight or less, more preferably 10% by weight or less, and even more preferably 8% by weight or less. Also, it is preferably 0.5% by weight or more, and more preferably 1% by weight or more.

[0014] (Medium-chain fatty acid content in protein drinks) In the present invention, the medium-chain fatty acid generally refers to a saturated fatty acid having 6 to 12 carbon atoms, but the medium-chain fatty acid in the present application is one having 8 to 10 carbon atoms. Generally, edible fats and oils are composed of triacylglycerol, which is formed by esterifying glycerin with three fatty acid molecules. Fats and oils are composed of triacylglycerols, and in the present application, the term "fats and oils containing medium-chain fatty acids" refers to a state in which medium-chain fatty acids constitute triacylglycerols. Medium-chain fatty acids must be contained in an amount equivalent to 0.1 to 5% by weight of the protein beverage, and are blended as fats and oils containing medium-chain fatty acids. Medium-chain fatty acids alone may adversely affect the flavor, so medium-chain fatty acids must be present as fatty acids that make up triacylglycerol. Three fatty acid molecules are bonded to triacylglycerol, and it does not matter whether all three molecules are medium-chain fatty acids or only some of them, as long as the medium-chain fatty acids satisfy the above-mentioned requirement of 0.1 to 5% by weight in the protein beverage. However, since natural fats and oils contain medium-chain fatty acid components, such as coconut, in very small amounts, they are often hydrolyzed to produce fatty acids, which are then esterified again with glycerin to produce medium-chain fatty acid oils and oils containing high purity medium-chain fatty acids (hereinafter referred to as MCT, with almost all of the constituent fatty acids being medium-chain fatty acids). In the present invention, the content of MCT relative to the total amount of fat and oil may be used to determine the amount of fat and oil. As described above, the medium chain fatty acid content, or MCT content, is 0.1 to 5% by weight, and preferably 0.5 to 3% by weight, based on the total weight of the protein drink. If the amount is less than 0.1% by weight, it becomes difficult to suppress the off-flavor of protein. Also, while there is no particular upper limit in terms of physical properties as long as the fat and oil can be emulsified, if it exceeds 5% by weight, the oiliness becomes strong, and the relatively expensive MCT may increase the cost of the protein drink itself. In addition, although the conditions for blending are as described above, the fats and oils containing medium-chain fatty acids must be blended before the protein beverage is heat-sterilized, as the effect of reducing the off-flavor of protein is poor after heat-sterilization.

[0015] (Amount of ethanol in protein drinks) In the present invention, it is preferable that the protein beverage contains ethanol. The ethanol in the present invention is not limited to pure ethanol, and any ethanol-containing ethanol can be suitably used, but distilled liquor is particularly preferable. Distilled liquor refers to liquor that has undergone a distillation process, such as shochu, shochu, whiskey, brandy, vodka, rum, tequila, liqueur, spirits, etc. In other words, non-volatile components that have undergone a brewing process have been removed by distillation, and these are hardly mixed in. In general, the ethanol concentration is high, and even if the amount added is small, the amount of ethanol added is large, and when the ethanol concentration after distillation is high, the flavor of the barrel is transferred when the product is aged in a barrel, etc., so that the off-flavor of protein can be reduced. Among them, brandy is preferable because of its ease of availability and compatibility with the off-flavor of protein. In the following regulations, ethanol is calculated as pure ethanol. In other words, for distilled alcohol with an ethanol purity of less than 100% by weight, the amount of distilled alcohol added is multiplied by the alcohol content. Furthermore, the manufacturing method of the present invention is characterized in mixing the above-mentioned ethanol at 0.05 to 1.5% by weight based on the total amount of the vegetable protein beverage, and by mixing it at a more preferably 0.07 to 1.2% by weight, and even more preferably 0.1 to 0.8% by weight, the flavor improving effect of the present invention can be further exerted. If the amount of ethanol mixed is less than 0.05% by weight based on the vegetable protein, it is difficult to obtain the effect of reducing undesirable flavors. Furthermore, if the amount of ethanol mixed exceeds 1.5% by weight relative to the vegetable protein, not only will undesirable flavors be reduced, but the good flavors inherent to the raw materials will also be reduced, and there is a risk that the alcohol flavor will remain even after heat sterilization. In addition, although the conditions for blending are as described above, when ethanol is blended, it must be blended before the protein drink is heat sterilized, since the effect of reducing the off-flavor of the protein is poor after heat sterilization.

[0016] (Production mode of protein beverage) The protein beverage of the present invention is prepared by mixing the above-mentioned protein ingredient with any aqueous phase component, for example water, and dissolving the mixture. An oil or fat containing medium-chain fatty acids and preferably ethanol are then added and homogenized. The order of addition of the aqueous phase component, the oil or fat, the ethanol, etc. does not affect the effect of the beverage. There are no limitations on the homogenizing device, but examples include a high-pressure homogenizer, a homomixer, a clearmix, and a nanomizer.

[0017] (heat sterilization) After homogenization, the protein beverage needs to be heat sterilized. The heat sterilization method can be any commonly used sterilization method, but it is preferably direct heating, and more preferably has a steam injection step and a degassing step. Here, the heating process is roughly divided into direct heating and indirect heating, and among the direct heating methods, the method of blowing steam directly into the object to be heated is preferable, and examples include VTIS, infusion, and injection. The degassing process is a process of removing steam and volatile components by reducing the pressure, and although there is no particular limitation, a pressure reducing device attached to the original VTIS may be used. The degassing step is preferably carried out simultaneously with or after the steam injection step.

[0018] The protein beverage obtained by the production method of the present invention has a reduced off-flavor and can be utilized as a liquid after heat sterilization as it is for beverage applications or as a liquid protein material. EXAMPLES

[0019] Hereinafter, examples of the present invention will be shown and described in more detail. Note that the numbers in the examples, except for the evaluation scores, represent weight standards.

[0020] <System of presence or absence of MCT and presence or absence of alcohol> (Examples 1 to 2, Comparative Examples 1 to 2) To water, a protein raw material (manufactured by Fuji Oil Co., Ltd., trade name: New Fuji Pro 1900, soy-derived isolated soy protein), MCT (manufactured by Fuji Oil Co., Ltd., trade name: MCT-64), and alcohol (95% by weight water-containing ethanol) were added and mixed and dissolved, and then high-speed stirring was performed in a preliminary emulsification tank at 60°C for 20 minutes to perform preliminary emulsification. Thereafter, for those without heating, homogenization was performed using a homogenizer to obtain an unsterilized protein beverage (before heating, Comparative Example 1). For those with heating, after preliminary emulsification, heating sterilization was performed at 140 to 150°C for 3 to 12 seconds using a VTIS sterilizer (manufactured by Iwai Kikai Kogyo Co., Ltd.) (direct steam injection method), followed by homogenization to obtain a sterilized protein beverage. The obtained protein beverage was described in accordance with Table 1 according to the flavor evaluation method. <Flavor evaluation method> Ten preference panelists were asked to taste the adjusted protein beverage, and the evaluation was performed using a 5-point scoring method with the evaluation target being whether they felt abnormal flavors such as an inappropriate bean odor or a green odor in the beverage. The average score was calculated and considered. Note that the scoring criteria were set such that the one considered by the panelists to have the least abnormal flavor was 5 points, the one considered by the panelists to have the most abnormal flavor was 1 point, and 1 to 5 points were assigned according to the degree of difference. And an average score of 3.5 points or more was set as the passing score. Separately, in the study of the protein content, as the protein content increased, the viscosity of the liquid increased, so the drinkability was also evaluated as an evaluation item.

[0021]

Table 1

[0022] Comparative Example 1, which is a conventional protein drink made by simply hydrating protein, and Comparative Example 2, which adds a heat sterilization process to Comparative Example 1 because heat sterilization is required for distribution, did not improve the off-flavor, and the unique "grassy" odor of soybeans was felt. However, Example 1, which was subjected to a sterilization process after adding MCT, had a clear improvement effect on the off-flavor. MCT has a milky flavor and has a strong effect of masking off-flavors even in small amounts, and it is thought that by mixing it with soybeans before heating, it has the effect of suppressing the generation of off-flavors during heating. Furthermore, when alcohol was added together with MCT and then sterilized by heating, in addition to the masking effect of MCT, this had the effect of reducing the grassy smell peculiar to soy protein itself, and was able to more effectively suppress off-flavors.

[0023] <Alcohol content system> (Examples 2 to 6) In Examples 2 to 4, protein drinks were produced using the same formulation and process as in Example 1, except that the amount of alcohol was changed as shown in Table 2. In addition, a protein beverage was produced using the same formulation and process as in Example 2, except that the alcohol in Example 6 was replaced with brandy (Suntory Brandy-Based Liqueur VO for Confectionery, manufactured by Suntory Spirits Limited, alcohol content 39%). The resulting protein beverage was evaluated and the results are shown in Table 2. For comparison, Example 1 is also listed in Table 2.

[0024] [Table 2]

[0025] Although the effect of Example 3, in which the alcohol content was 0.05% by weight, was weaker, it was confirmed that the off-flavor suppressing effect was greater than that of the additive-free Example 1. In Examples 2 and 4, the suppressing effect was adequate. Moreover, in Example 6, in which brandy was used as the alcohol, the amount of alcohol was about the same as in Example 2, but the effect of suppressing off-flavors was particularly large.

[0026] <System for examining the amount of MCT> (Examples 7 and 8) Protein beverages were prepared in the same formulation and process as in Example 6, except that the amount of MCT was changed as shown in Table 3 for Examples 7 and 8. The obtained protein beverages were evaluated and shown in accordance with Table 3. For comparison, Example 6 was also described in Table 3.

[0027]

Table 3

[0028] Although Examples 6, 7, and 8 each had an extremely high effect of suppressing off-flavors, in Example 7 where the amount of MCT was 1% by weight, which was less than that in Example 6, the off-flavor suppression effect was not much different from that in Example 6 due to the masking effect by the brandy flavor. Although the suppression effect in Example 8 was also appropriate, it was not stronger than that in Example 6 considering the relatively large amount of MCT, and moreover, the oiliness and cost increased as the amount of MCT increased.

[0029] <System for examining the amount of protein> (Examples 9 to 11 and Comparative Example 3) Protein beverages were prepared in the same formulation and process as in Example 6, except that the amount of protein was changed as shown in Table 4 for Examples 9 to 11 and Comparative Example 3. Note that alcohol and MCT were adjusted to the same ratio as in Example 6 with respect to the amount of protein. The obtained protein beverages were evaluated and shown in accordance with Table 4. For comparison, Example 6 was also described in Table 4.

[0030]

Table 4

[0031] Although the effects of suppressing off-flavors were extremely high in Examples 6, 9, 10, and 11, Example 9 may not be able to achieve the target quality of the final product if the commercial product is targeted to have a high protein content. In addition, since the protein content is low, the off-flavor content is low, and even if the effect of the present invention is exerted, it is difficult to evaluate it. Although the protein concentration in the beverages of Examples 10 and 11 was high, the off-flavor was significantly suppressed and the beverages were drinkable. However, the viscosity of Comparative Example 3 increased, making the beverage difficult to work with.

[0032] <Protein origin study system> (Examples 12 and 13) In Examples 12 and 13, protein drinks were prepared using the same formulation and process as in Example 6, except that the origin of the protein was changed as shown in Table 4. The obtained protein drinks were evaluated and the results are shown in Table 5. For comparison, Example 6 is also listed in Table 5. The pea protein used was "PP-CS" (product name, Organo Foodtech Co., Ltd., protein content 80%), and the milk protein used was "WPC80" (product name, Warrnambool Cheese & Butter Pty Ltd., protein content 76.5%).

[0033] [Table 5]

[0034] Examples 6, 12, and 13 each had an extremely high effect of suppressing off-flavors. The pea protein of Example 12 tended to produce an off-flavor that was different from that of the soy protein of Example 6 (less astringent but slightly grassy), but it was confirmed that the off-flavor could be suppressed to the same extent as that of the soy protein. Also, although milk protein itself does not have as strong an off-flavor as soy protein or pea protein, depending on the storage conditions and place of origin, it may have a slight Maillard odor or animal odor, but the masking effect provided by MCT is sufficient. [Industrial Applicability]

[0035] By using the present inventors' manufacturing method, it is possible to provide a protein beverage with good flavor and reduced off-flavors, without the need to add many new steps.

Claims

1. A method for producing a protein drink containing isolated soy protein, comprising mixing medium-chain fatty acids equivalent to 0.1-5% by weight of the protein drink and 0.05-1.5% by weight of ethanol relative to the protein drink, and heat sterilizing the mixture, wherein the medium-chain fatty acids are used in a state in which they form triacylglycerol. Ethanol is a distilled alcoholic beverage. The protein beverage also excludes the embodiment using soybean powder, the embodiment using coffee and high acyl gellan gum, and the embodiment using lactalbumin.

2. A method for producing a protein beverage as described in claim 1, which contains 1 to 12 weight percent isolated soy protein.

3. The method for producing a protein drink according to claim 1 or 2, wherein the protein drink is sterilized by heating at 80°C to 160°C for 2 seconds to 60 minutes.

4. 4. The method for producing a protein drink according to claim 1, wherein the heat treatment comprises a direct heating step and a deaeration step.

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