JP4525339B2 - Sterilized raw milk and its production method - Google Patents

Description

  The present invention relates to a raw sterilized soymilk, a method for producing the same, and a soymilk product using raw sterilized soymilk as a raw material.

In recent years, the effect of soy protein to lower cholesterol has been clarified, and along with this, interest in traditional soy milk, tofu, yuba, prepared soy milk, soy milk drinks, and various other soy milk products has rapidly increased. The standards for drinking soymilk, prepared soymilk and soymilk drinks are defined by the Japanese Agricultural Standard (Non-Patent Document 1).

At the same time, soybean milk with improved flavor and texture has been developed in recent years. For example, Patent Document 1 discloses a method for improving soymilk odor and obtaining a soymilk with a clean texture. On the other hand, consumers have a wide variety of preference trends, and conversely, soy milk that also has the original taste and richness of richness of soybeans may be preferred depending on the age group and scene of food.

Conventionally, the following methods are usually used as methods for imparting a rich feeling to soy milk.
(A) A method of concentrating soy milk to increase the solid content.
(B) A method of increasing the viscosity of soy milk by adding a thickener to soy milk.
(D) A method in which okara is refined and dispersed without separating okara.

However, in the method (a), insoluble substances increase and the sterilization apparatus is likely to be attached or burnt during sterilization. Also, depending on the sterilization method, no matter how much the solid content is increased, the viscosity is lowered and a rich feeling cannot be obtained. In the method (b), there is a problem that even if a rich feeling is obtained, a different paste is produced which is different from the rich taste of soybean or soy milk itself. The method (c) also increases the solid content and gives a rich feeling, but because it contains the insoluble fiber of okara, no matter how refined it is, it feels rough and the throat feels so bad that the soy milk is dry However, there was a problem that the soymilk itself lacked its richness.

JP 10-295308 A JP 59-059151 A Japanese Patent Laid-Open No. 02-257831 JP-A-11-2221039 JP 2002-281828 A December 19, 2000 Ministry of Agriculture, Forestry and Fisheries Notification No. 1684

Accordingly, an object of the present invention is to provide a refreshing soy milk that is provided with the richness (boiled taste) of soy milk itself and the original umami taste of soybeans without causing the above-mentioned problems and has no miscellaneous taste. is there.

As a result of intensive studies in view of the above problems, the present inventors have sterilized soy milk that has been separated in the low temperature range and sterilized by acting to the extent that the protein cross-linking enzyme does not coagulate on the raw squeezed soy milk that has not been exposed to the high temperature range Has a viscosity of 15 to 250 mPa · s at 10 ° C. without a decrease in viscosity due to sterilization treatment, and it has been found that the thick feeling and the original taste of soybeans are remarkably improved and also has a storage property.
Conventionally, there has been known a technique for reinforcing the coagulation force of a soymilk by a coagulant by allowing a protein cross-linking enzyme to act on soymilk (Patent Documents 2 to 5). The purpose is to improve and improve physical properties, and nothing is mentioned about improving the texture and flavor of soymilk itself as in the present invention.

From the knowledge obtained above, the present invention is as described below,
(1) Sterilized raw soymilk having a soybean solid content of 15% by weight or less, and having a viscosity at 10 ° C. of 15 to 250 mPa · s,
(2) The above description (1), wherein a protein cross-linking enzyme is allowed to act on soymilk obtained by the raw squeezing method or kure before being separated from soymilk and okara by the raw squeezing method, and then sterilized. Of raw squeezed soymilk,
(3) The method for producing freshly squeezed soymilk according to (2) above, wherein the sterilization is performed by an indirect sterilization method, a direct steam injection method or a retort method,
(4) a soy milk product made from the raw squeezed soy milk described in (1) above,
(5) The above (4), wherein the soy milk product is selected from the group consisting of soy milk, tofu, prepared soy milk, soy milk drink, soft drink, soy milk pudding, soy milk jelly, soy milk soup, tofu pudding, tofu jelly, tofu soup, yuba and sugar beet. ) Soy milk products,
Is disclosed.

According to the present invention, the soymilk's original umami and richness (kokumi) is exhibited even in the range of the normal solid content (7 to 15% by weight) of soymilk, and the bean odor that could not be solved by the conventional soymilk manufacturing method As a result, it has become possible to obtain a sterilized soy milk having a good flavor and a refreshingly reduced quality.

The present invention is described in detail below.
In the present invention, the sterilized soymilk is a soymilk in which microorganisms in the soymilk, particularly heat-resistant bacteria, have been completely killed by heat treatment at a high temperature, and if this is hermetically sealed and filled, it is usually at room temperature or refrigerated for 3 months. Soy milk that can be stored for a long time. Therefore, it is distinguished from soy milk that has been sterilized and can be stored refrigerated for only a few weeks. In order to sterilize heat-resistant bacteria in soymilk, it is preferable that at least the F value is 4 (min) or more, preferably 10 (min) or more, more preferably 20 (min) or more. In addition, F value shows the heating time (minute) required to kill a fixed number of bacteria at 121 degreeC.

The freshly squeezed soymilk of the present invention is a product obtained by sterilizing soymilk extracted from soybeans by a raw squeezing method, and has a soybean solid content of 15% by weight or less, more preferably 7 to 15% by weight. The viscosity at 15 ° C. is 15 to 250 mPa · s. The soybean solid content is more preferably 8 to 14% by weight, and further preferably 9 to 12% by weight. The viscosity at 10 ° C. is more preferably 20 to 250 mPa · s. In the case of soymilk by a normal manufacturing method, if sterilization is performed, the viscosity will be at most 15 mPa · s at the same solid content, but this sterilized soymilk retains the above viscosity range even if sterilization is performed. It has a rich feeling (kokumi) that is not found in soymilk by a normal manufacturing method. In the present invention, the viscosity of soy milk can be represented by a value measured with a B-type viscometer at 10 ° C.

In other words, without adding soy milk powder, adding soy protein powder, increasing soy solids without separating okara, or using a thickener, It has a soy solid content concentration that does not change, and is a sterilized soy milk but has a natural thick feeling that does not give a sense of incongruity. In addition, this sterilized soymilk uses soymilk extracted by the raw squeezing method as a raw material, so that the original umami taste is imparted to the rich feeling, and the flavor of the soymilk is synergistically improved.

If the soy solid content is less than 7% by weight, a large amount of protein cross-linking enzyme must be added to obtain a viscosity and richness. If it exceeds 15% by weight, the reaction with the protein cross-linking enzyme will increase the viscosity too much and cause aggregation. Coagulation is likely to occur. By the way, so long as it is within the above range, adding soymilk powder or powdered soy protein or concentrating to adjust the solid content is not hindered. However, even if an attempt is made to give a rich feeling by simply increasing the solid content, if the sterilization treatment by the direct steam injection method is performed, the viscosity is lowered, and a sufficient rich feeling cannot be obtained. For example, when sterilization is performed on soy milk having a soybean solid content of 9% by weight, the viscosity becomes 8 mPa · s. When soy milk having a soy solid content of about 13% by weight is boiled and heated (100 ° C.), the viscosity increases to about 40 mPa · s. However, when soy milk having a soybean solid content of about 13% by weight is sterilized, the viscosity immediately decreases to 15 mPa · s or less, a rich feeling cannot be obtained, and the effect of increasing the soybean solid content is hardly exhibited. The reason why the viscosity decreases when sterilization is performed at such a high temperature is not certain, but the increase in viscosity when concentrated is probably due to the hydrophobic bond between protein molecules with relatively weak binding force. It is presumed that it is easily cut by energy.

[Manufacturing aspect of the raw squeezed soy milk of the present invention]
As raw materials of the raw squeezed soymilk of the present invention, soybeans, soybean powder, defatted soybean powder and the like can be used, but it is appropriate to use soybeans as a raw material. In order to remove the miscellaneous taste, soy-dehulled hypocotyl soybean from which the seed coat and hypocotyl part have been removed in advance is more suitable. Moreover, it does not specifically limit as a kind of soybean, A yellow soybean, a white soybean, a black soybean, a green soybean, etc. can be selected variously.

In the production of the sterilized soymilk of the present invention, in order to obtain soymilk from soybeans, a method called so-called “raw squeezing method” is used that separates soymilk and okara without heating kure at a high temperature. . By adopting such a method, the umami of soybeans can be extracted as it is, with less miscellaneous taste than the “squeezing method” of heating at a high temperature. Specifically, soybean is soaked in water to form a swollen soybean, which is pulverized by a known atomization means to obtain a suspension (hereinafter referred to as “Kure”), and heated at a high temperature. Alternatively, a method of obtaining soy milk by performing solid-liquid separation with a centrifuge or the like to remove insoluble residues corresponding to okara can be used.

As a means of atomization, a grinder or the like used for the production of ordinary soymilk can be used, and it is not particularly limited. However, because polysaccharides are extracted from the cell walls of soybean by grinding, soy bean tends to remain. In particular, as described in Patent Document 1, swollen soybeans are first shredded smoothly with a rotary blade type shear force such as a commit roll (manufactured by URSCHEL) to reduce the average particle size to 100 microns or less. Can be used. Further, if necessary, a method of reducing the average particle size to 15 to 40 microns by applying a frictional shearing force such as a homogenizer can be used. Soymilk prepared by such a method has a uronic acid content of 3.5 mol% or less, and is less extracted from polysaccharides from the cell walls of soybean, and has a better flavor in synergy with the raw squeezing method.

The raw squeezing method is generally a method in which soybeans are soaked in water and ground to separate soy milk and okara from kure, and the method is carried out at a low temperature without heating at a high temperature. It is appropriate to separate at -40 ° C, preferably 5-35 ° C, more preferably 5-30 ° C, even more preferably 5-25 ° C, most preferably 5-20 ° C. When separated in such a temperature range, the original umami taste of soybeans can be easily extracted, and the color of soy milk becomes white and excellent in appearance. When the temperature at the time of separation is too high, the miscellaneous taste of the obtained soymilk becomes strong and the original taste of soybeans decreases. Moreover, when using soy milk, the color tone tends to be yellowish.

In order to obtain the sterilized soymilk of the present invention, it is important to undergo a step of allowing a protein cross-linking enzyme to act on swollen soybeans and kure before being separated from soymilk and okara by the raw squeezing method, or the raw squeezed soymilk after separation. . That is, the raw material in the process of obtaining soybeans by immersing soybeans in water, the obtained swollen soybeans, the process of pulverizing the swollen soybeans to obtain kure, the obtained kure, and the raw squeezing method from kure It is preferable to act on the soy milk obtained during the process of separating soy milk and okara. In this way, by allowing the protein cross-linking enzyme to act on raw squeezed soymilk or the like, sterilized soymilk having both a rich feeling and the original taste of soybeans can be obtained even when sterilized. However, if an enzyme is allowed to act in the process before separating the okara, the protein in the okara and the protein in the soy milk are cross-linked or the yield of soy milk tends to decrease, so It is particularly preferable to act on freshly squeezed soymilk obtained by separation. When a protein cross-linking enzyme is not allowed to act, a rich feeling cannot be imparted.

The protein cross-linking enzyme is not particularly limited as long as it is an enzyme that catalyzes cross-linking of protein molecules. For example, a glutamine residue [-(CH2) 2-CO-NH2] and a lysine residue [NH2- Examples include those that catalyze reactions involving an ε-amino group, such as a condensation reaction of (CH2) 4-] and a condensation reaction of an asparagine residue [—CH2—CO—NH2] and a lysine residue. Moreover, although an amino group is not involved, what catalyzes the condensation reaction between thiol groups (-SH) of cysteine residues can also be used. These covalent bonds are very strong and are not easily broken by heat treatment energy at high temperatures. Specifically, transglutaminase (EC2.3.2.13) that catalyzes the condensation of glutamine and lysine residues and thiol that catalyzes the formation of disulfide bonds (-S-S-) by condensing thiol groups. And disulfide exchange enzyme (protein disulfide-isomerase, EC5.3.4.1). Practically, it is preferable to use transglutaminase. The origin of transglutaminase is not particularly limited, and any of those derived from animals, microorganisms, and plants can be used. A purified enzyme may be used, and a commercially available preparation may be used.

The reaction conditions for the protein cross-linking enzyme can be appropriately selected by those skilled in the art. For example, in the case of transglutaminase, preferable reaction conditions are as follows. It is appropriate that the amount of transglutaminase used is such that the viscosity of soy milk increases excessively and does not cause coagulation or water separation, that is, does not cause gelation. Specifically, the transglutaminase activity (hydroxamate method) is suitably 1.4 to 6.7 units, preferably 2.7 to 6.0 units per gram of soymilk protein. If the amount used is too small, a predetermined viscosity cannot be obtained after sterilization, resulting in a sterilized soymilk with an insufficient thick feeling. On the other hand, if the amount used is too large, it solidifies and waters off like tofu and is not suitable as a beverage. The pH of the soy milk is not particularly required to be adjusted, and may be adjusted at a neutral pH, but can be usually adjusted to pH 5 to 9, preferably 6 to 8. If the pH is too low or too high, the enzyme is deactivated and it is difficult to obtain a predetermined effect. The reaction temperature is suitably 0 to 80 ° C, preferably 20 ° C to 70 ° C, more preferably 40 ° C to 60 ° C. If the temperature is too low, it takes too much reaction time to reach a predetermined viscosity, and if the temperature is too high, the enzyme is deactivated. The reaction time varies depending on the amount of enzyme used and the temperature, but is preferably 5 minutes to 3 hours, and preferably about 10 minutes to 2 hours.

Next, the soy milk subjected to the enzyme reaction by the above method is sterilized. As the sterilization apparatus, a high-temperature instantaneous sterilization (UHT) apparatus can be used, and either an indirect heating apparatus such as a plate-type heat exchange apparatus or a scraping-type heat exchange apparatus, or a direct heating apparatus can be used. In the heat exchanger, the solid content tends to gradually adhere to the inside of the pipe as the soybean solid content becomes high, so care must be taken such as washing. The direct heating device is less preferable for such a scaling, and the direct steam injection method is particularly preferable because it has a deodorizing effect on soy milk because vacuum treatment is performed after steam is blown. Moreover, although it is different from the UHT device, retort sterilization can be sterilized. However, since it takes a long time for sterilization, it is used under the condition that flavor and browning of soy milk do not occur.

In order to sterilize heat-resistant bacteria in soymilk, at least F value corresponding to 4 (minutes), preferably 10 (minutes) or more, more preferably 20 (minutes) or more is applied. preferable. In order to satisfy such conditions, in the case of UHT, the temperature for sterilization is 122 to 160 ° C, preferably 125 to 160 ° C, more preferably 135 to 160 ° C, and further preferably 140 to 160 ° C. It is. If it is lower than 122 ° C, it is difficult to sterilize heat-resistant bacteria in soybean, or it takes a long time for sterilization. Moreover, when it exceeds 160 degreeC, a deterioration of a flavor, a burn, etc. are easy to arise. The heating time for sterilization may be set so that the F value satisfies the above conditions in the above temperature range, but it is usually 2 seconds to 30 seconds, preferably 4 seconds to 10 seconds. If it is shorter than 2 seconds, sterilization is not sufficient, and if it exceeds 30 seconds, problems such as deterioration of flavor, scorching, and coloring may occur. Also in the case of retort sterilization, the F value can be carried out at a temperature and time satisfying the above conditions.

Sterilized raw soymilk can be cooled to 10 ° C or lower and filled aseptically, or hot-packed and marketed as sterilized soymilk as it is, or as soymilk for raw materials for various soymilk products Supply is possible. And since it is sterilized, it can be stored at room temperature or refrigerated for 3 months or longer.

The raw squeezed soymilk obtained as described above retains its richness even when sterilized, and is given the original umami and richness (kokumi) that are not found in normal soymilk. The texture is good.

In other words, it is concentrated to give soy milk a rich feeling, soy solid content is increased without separating okara, or even without adding a thickener, soy solid content concentration is the same as normal soy milk, And although it is a sterilized soymilk, it has a rich feeling without discomfort. Moreover, by combining the raw squeezing method and the action of protein cross-linking enzymes, the unique bean odor has been dramatically improved while retaining the flavor and richness of soybeans that could not be resolved by conventional soymilk production technology. It has a very good flavor.

As one method of using the freshly squeezed soymilk of the present invention, the manufacturer can use this as a soymilk raw material as it is, or prepare soymilk, soymilk beverages or soft drinks by preparing soybean solids and other raw materials. Can do. In particular, the higher the soy solid content, the more the richness of the squeezed soymilk and the original flavor of soybeans are utilized.

As another method of using the raw sterilized soymilk of the present invention, the manufacturer adds a commonly used coagulant such as bittern, magnesium chloride, calcium chloride, calcium sulfate, glucono delta lactone as a raw material for tofu. And tofu can be produced. The kind of tofu may be silken tofu or cotton tofu, and cut tofu, filled tofu, rag tofu, frozen tofu, etc. can be employed.

It is well known that sterilized soy milk, which has been pasteurized at high temperatures, is poorly gelled due to heat denaturation of the protein, and does not produce tofu with sufficient hardness even when heated with the addition of a coagulant for tofu. Yes. However, since the raw sterilized soymilk of the present invention is polymerized by a protein cross-linking enzyme, heat resistance is imparted, and a decrease in gelling power after high-temperature sterilization is suppressed. Tofu with sufficient hardness can be prepared by adding a coagulant and heating. The obtained tofu is characterized in that it has a rich taste that is similar to the original taste and milky taste of soybeans by a combination of raw squeezing method, protein cross-linking enzyme treatment and sterilization treatment.

If tofu is produced using the raw squeezed soymilk of the present invention as a raw material, it can be easily produced with a microwave oven or steamer at home so that it can have a delicious taste and rich taste of soybeans. Can be prepared. This is also because it is sterilized and has good storage stability, and the coagulation reaction by the coagulant for tofu is easily controlled by the protein cross-linking enzyme treatment.

Further, the manufacturer can use this sterilized soymilk as a soymilk material for the production of various other soymilk products that can enhance the original umami and richness of soybeans. For example, lactic acid fermented soy milk, acidic soy milk beverage, soy milk alcoholic beverage, pudding, soup, jelly, frozen confectionery, baked confectionery, Japanese confectionery, sugar-coated confectionery, snack, bread, cake, yogurt, cheese, cream, custard cream, filling, chocolate, spread It can be used for mayonnaise, sauces, fried foods, marine products, livestock meat products, etc., and is not limited to such examples. Furthermore, a coagulant is allowed to act on the sterilized soymilk to produce tofu or a paste-like or liquid tofu equivalent thereto, and then it can be used for the above-mentioned various products. In this case, it is called tofu pudding or tofu soup.

In addition, when using the freshly squeezed sterilized soy milk of the present invention for the above-mentioned soy milk product, raw materials other than the soy milk of the soy milk product can be mixed and dissolved in advance before sterilization to prepare a sterilized premix of the soy milk product. In this case, the raw materials other than soy milk can be mixed either before or after the protein cross-linking enzyme is allowed to act, but it is preferable to mix them after the action of the protein cross-linking enzyme. Foods such as fruit juice, vegetables, sweeteners, seasonings, thickeners such as starch and thickening polysaccharides, fats and oils, coagulants, dietary fiber, vitamins, minerals, flavorings, acidulants, emulsifiers, etc. Food materials and food additives that are generally used can be used. In this case, in order to supply to a subsequent sterilization step, it is preferable to homogenize with a homogenizer or the like to make it liquid. In the case of a sterilized premix, the soybean solid content range (7 to 15% by weight) and the viscosity range (15 to 250 mPa · s) specified in the case of 100% freshly squeezed soymilk may be out of range. However, it is a matter of course that this case is not excluded as long as the technical idea of the present invention is met.

As described above, the freshly squeezed sterilized soymilk of the present invention may be used for the production of various soymilk products as a soymilk material, and the sterilized soymilk of the present invention is substantially produced during the process of producing the various soymilk products. Of course, the process may be included. For example, raw materials other than soy milk of soy milk products can be added to and mixed with a solution obtained by allowing transglutaminase to act on soy milk, then sterilized, and this sterilized liquid can be continuously processed into various soy milk products.

Examples of the sterilized soy milk of the present invention will be described below, but it goes without saying that the technical idea of the present invention is not limited by such description. In the following description, “%” means “% by weight”.

[Example 1] Manufacture of raw squeezed soymilk Swelled soybeans (water content 40) with 10 parts of water added to 1 part by weight (hereinafter referred to as "parts") of dehulled hypocotyl soybeans and immersed for at least 60 minutes at 20 ° C. ~ 55%) 1 part of water (15 ° C) added 3 parts finer with a grinder (Masuyuki Sangyo Co., Ltd.) while maintaining a temperature of 15 ° C to obtain a grinding liquid (Kure) . It processed with 3000G for 5 minutes with the centrifuge, the soymilk and the okara were isolate | separated at 15 degreeC, and the raw squeezed soymilk was obtained. This freshly squeezed soymilk had a solid content of 9.0%, a protein content of 4.5% and a pH of 6.8.

Next, while maintaining the obtained soy milk at 60 ° C., 0.15 g of transglutaminase preparation “Activa Supercard” (Ajinomoto Co., Inc.) per 1 g of soy milk protein (transglutaminase 0.2%, reduced maltose powder, etc. 99.8%, enzyme titer 17-26 units / g) was allowed to act for 30 minutes. Immediately after the reaction, supply directly to a sterilization apparatus (direct heating apparatus) by direct steam injection, sterilize at 150 ° C for 4 seconds (F value equivalent to 51.7 minutes), cool to 10 ° C, and aseptically packaged Filling was performed to obtain a raw squeezed sterilized soymilk. As a control, instead of raw squeezed soymilk, hot water (90 ° C) was added and kept at 90 ° C, using the squeezed soymilk separated from soymilk and okara. Obtained (Comparative Example 1).

The resulting freshly squeezed soymilk has a soybean solid content of 9.0% and a viscosity at 10 ° C. of 22 mPa · s, a strong soybean taste, a natural richness, and surprisingly, The unique bean odor, which could not be eliminated by the manufacturing technology, disappeared, and it had a very good flavor. On the other hand, the boiled and sterilized soymilk of Comparative Example 1 also had a rich feeling and a flavor similar to that of the freshly squeezed milk, but the freshly sterilized soymilk was superior in terms of the original taste of soybeans. It was hard to feel the unique bean odor.

[Example 2] Production of sterilized soymilk After transglutaminase was allowed to act on soymilk in the same manner as in Example 1, it was immediately supplied to a plate-type sterilizer (indirect heating device) and sterilized at 150 ° C for 4 seconds. Sterile soymilk was obtained. The obtained sterilized soymilk had a soy solid content of 9.0%, and a thick feeling equivalent to that of Example 1 was obtained. The flavor was also good, but Example 1 was more effective in improving the bean odor.

[Test Example 1] Effect of Soybean Solid Concentration on Concentration of Sterilized Soymilk In the same manner as in Example 1, raw squeezed soymilk was produced without the protein cross-linking enzyme acting. The obtained soymilk was concentrated and adjusted to the soy solid content concentration shown in Table 1 (tests 1 to 4), and the effect of increasing the soy solid content concentration on the richness of the raw squeezed soymilk was examined. These were supplied directly to a sterilization apparatus using a steam injection method, and sterilized at 150 ° C. for 4 seconds. As in Example 1, sterilized soymilk was obtained. Table 1 shows the soy solid content of the obtained soymilk, the viscosity at 10 ° C. (B-type viscometer), the storage stability, and the presence or absence of a bean odor.

(Table 1)
─────────────────────────────────
Examples Test Test Test Test
1 1 2 3 4
─────────────────────────────────
Enzyme reaction Yes No No No No Soy solids 9% 9% 11% 13% 16%
─────────────────────────────────
Viscosity (mPa · s) 22 7 9 12 14
Rich feeling ◎ × × × ○
Bean odor ◎ ○ ○ ○ ○
Preservability ◎ ◎ ◎ ◎ ◎
─────────────────────────────────
(Evaluation criteria)
・ Dense feeling / ◎ Very good, ○ Good, △ Acceptable, × Not possible ・ Bean odor / ◎ Very little, ○ Less, △ Slightly more, × Very much ・ Preservability (storage stability at room temperature for 3 months) / ◎ Very good, ○ Good, △ Yes, × No

Although all tests 1 to 4 in which the protein cross-linking enzyme was not allowed to act were sterilized, no matter how much the soybean solid content was increased, the viscosity was not felt as in Example 1 and a sufficient rich feeling was not obtained. From the above results, even if the soybean solid content was increased, a thick feeling was not sufficiently obtained when sterilization was performed. In addition, when the soy milk of Tests 1 to 4 was separately sterilized with a plate sterilizer, in Test 3 and Test 4, the solid content of the soy sterilizer was attached or burnt due to the high soybean solid content, and stable sterilization occurred. It was difficult to process.

[Test Example 2] Effect on the quality of sterilized soymilk by the sterilization method Raw squeezed soymilk was produced in the same manner as in Example 1 with or without the action of the protein cross-linking enzyme. And the influence on the quality of sterilized soymilk by soybean solid content and sterilization method (direct heating, indirect heating, retort, boiling, unheated) was examined (tests 5 to 9 in Table 2). Evaluation was carried out in the same manner as in Test Example 1. In addition, F value of test 5 was about 10 (min).

(Table 2)
────────────────────────────────────
Example Example Test Test Test Test Test
1 2 5 6 7 8 9
────────────────────────────────────
Enzyme reaction Yes Yes Yes No No No Soy solids 9% 9% 9% 9% 9% 13% 16%
────────────────────────────────────
Heating method Direct Indirect Retort Unheated Boiling Boiling Boiling Heating temperature 150 ℃ 150 ℃ 125 ℃ −100 ℃ 100 ℃ 100 ℃
Heating time 4 seconds 4 seconds 15 minutes − 3 minutes 3 minutes 3 minutes ──────────────────────────────────── ─
Viscosity (mPa · s) 22 31 32 10 12 26 35

Rich feeling ◎ ◎ ◎ × × ○ ◎
Bean odor ◎ ○ ○ △ △ △ △
Preservability ◎ ◎ ◎ × × × ×
────────────────────────────────────

From the result of Test 5, when the enzyme was allowed to act also in retort sterilization, the rich feeling was the same as in Example 1, and a rich feeling was obtained. However, the boiled bean odor peculiar to conventional soymilk did not disappear by boiling (Tests 7 to 9). Furthermore, boiling did not have any storage stability at room temperature for 3 months, and a sterilized soy milk having a rich feeling could not be obtained. Further, when the solid content of soybean was increased, a thick feeling similar to that of Example 1 was obtained when the solid content was increased as in Tests 8 and 9. However, the bean smell was strong and the quality with good flavor could not be obtained. Moreover, there was no shelf life at room temperature for 3 months, and sterilized soymilk that retained a rich feeling could not be obtained by boiling sterilization. From the above results, it is considered that a combination of raw squeezing method, action of protein cross-linking enzyme and sterilization treatment is indispensable for obtaining a sterilized soy milk that has a rich feeling, has a very low bean odor, and can be stored.

[Test Example 3]
Raw squeezed soymilk was produced in the same manner as in Example 1. At this time, per 1 g of soy milk protein of transglutaminase preparation “Activa Super Card” (manufactured by Ajinomoto Co., Inc.) (transglutaminase 0.2%, reduced maltose powder and others 99.8%, enzyme titer 17-26 units / g) The amount of protein added was changed as shown in Table 3, and the effect of the amount of protein cross-linking enzyme on the quality of sterilized raw milk was tested (tests 10 to 15). Evaluation was carried out in the same manner as in Test Example 1.

(Table 3)
─────────────────────────────────────
Examples Test Test Test Test Test Test
1 10 11 12 13 14 15
─────────────────────────────────────
Formulation addition amount (g) 0.15 0.0 0.05 0.10 0.15 0.20 0.40
─────────────────────────────────────
Rich feeling ◎ × × ○ ◎ ◎ −
Bean odor ◎ ○ ○ ◎ ◎ ◎ −
Storage stability ◎ ◎ ◎ ◎ ◎ ◎ −
─────────────────────────────────────

As shown in Test 12, by adding 0.1 g or more of an enzyme preparation per gram of soymilk protein and reacting and sterilizing it, it was possible to obtain a freshly squeezed sterilized soymilk with a rich feeling and a very low bean odor. However, as shown in Test 15, when 0.4 g of the enzyme preparation was added per 1 g of soy milk protein and reacted, protein coagulation and water separation were observed and sterilization could not be performed. From the above results, in order to obtain a soy milk with a rich feeling and a very little bean odor and a sterilized soy milk, a reaction temperature of 60 ° C. and a reaction time of 30 minutes were used as a transglutaminase preparation (transglutaminase 0.2%). It is considered desirable to add 0.10 to 0.2 g per gram of soy milk protein and 1.4 to 6.7 units per gram of soy milk protein as transglutaminase activity (hydroxamate method).

[Example 3] Manufacture of sterilized squeezed prepared soymilk 0.15 g of transglutaminase preparation "Activa Super Card" (manufactured by Ajinomoto Co., Inc.) per gram of soymilk protein was added to the raw squeezed soymilk prepared in the same manner as in Example 1. And reacted at 60 ° C. for 30 minutes. To 100 parts of this soymilk, 3 parts of sugar, 1.3 parts of vegetable oil and fat, 0.3 part of salt, 0.1 part of emulsifier, 0.2 part of fragrance, and 23.7 parts of water are added and dissolved. The mixture was supplied to a homogenizer (manufactured by APV) and homogenized at 100 kg / cm2. Next, it was supplied directly to a sterilization apparatus using a steam injection method, sterilized at 150 ° C. for 4 seconds, cooled to 10 ° C., aseptically filled into aseptic packaging, and squeezed sterilized prepared soymilk. The obtained freshly squeezed sterilized soymilk has a soybean solid content of 7.0%, and as in Example 1, has a natural rich feeling different from a thick feeling with a sense of incongruity like a thickener, and is unique. The bean odor was not felt and it had a very good flavor.

[Example 4] Production of freshly squeezed soymilk beverage 0.15 g of transglutaminase preparation “Activa Super Card” (manufactured by Ajinomoto Co., Inc.) was added to freshly squeezed soymilk prepared in the same manner as in Example 1. And reacted at 60 ° C. for 30 minutes. To 100 parts of this soymilk, 15 parts of sugar, 2 parts of cocoa powder, 1.5 parts of vegetable oil and fat, 0.3 part of salt, 0.4 part of stabilizer, 0.2 part of fragrance, and 60.6 parts of water are added. Then, it was dissolved and supplied to a homogenizer (manufactured by APV) and homogenized at 100 kg / cm 2. Next, it was supplied to a sterilization apparatus using a direct steam injection method, sterilized at 150 ° C. for 4 seconds, cooled to 10 ° C., and aseptically packed in aseptic packaging to obtain a sterilized cocoa soy milk beverage. The obtained sterilized cocoa soymilk beverage has a soy solid content of 5.0%, and has a natural rich feeling different from a thick feeling with a sense of incongruity like a thickener as in Example 1, and a unique bean. The odor was not felt and it had a very good flavor.

[Example 5] Production of raw squeezed tofu 0.15 g of transglutaminase preparation "Activa Super Card" (manufactured by Ajinomoto Co., Inc.) was added to raw squeezed soymilk prepared in the same manner as in Example 1, The reaction was performed at 60 ° C. for 30 minutes. Subsequently, it was supplied to a sterilization apparatus by a direct steam injection method, sterilized at 150 ° C. for 4 seconds, cooled to 10 ° C., and aseptically filled (Example 5). Moreover, as a control, the boiled and sterilized soymilk of Comparative Example 1, the raw squeezed soymilk that was similarly sterilized without reacting with transglutaminase (Comparative Example 2), the transglutaminase treatment and the sterilization treatment were not performed, and only boiling was performed. Freshly squeezed soymilk (Comparative Example 3) was also prepared. When these were stored in a refrigerator at 10 ° C. or lower for 1 month, the raw squeezed soymilk of Comparative Example 3 was rotten and could not be used.
0.8 parts of a coagulant for tofu (Shionda bittern liquid: manufactured by Ako Kasei Co., Ltd.) is added aseptically to 100 parts of the freshly squeezed soymilk of Example 5, sealed in a container, and heated at 90 ° C. Heated in to complete the coagulation reaction and allowed to cool. The tofu obtained had a very strong original umami taste, no bean odor, sufficient hardness, a smooth and good texture, and a white and bright color tone. On the other hand, although the tofu made from the boiled and sterilized soymilk of Comparative Example 1 had sufficient hardness, it lacked the umami and had a yellowish color tone compared to Example 5. When the tofu was produced in the same manner with the freshly squeezed soymilk in which the transglutaminase of Comparative Example 2 was not reacted, it was in the form of rag tofu and was not sufficiently hardened.
From the above, the freshly sterilized soybean milk of Example 5 which is the present invention has both high storage stability, coagulation property and the original flavor of soybean, so that it is only suitable for the tofu manufacturing industry as a raw material for producing flavorful tofu. It can be easily used at home to make flavorful tofu.

Claims (5)

Raw squeezed milk der soy solids are sterilized in 15 wt% or less is, be one protein cross-linking enzyme is applied, squeezed raw wherein the viscosity at 10 ° C. is 15~250mPa · s Sterile soymilk. 2. The raw sterilization process according to claim 1, wherein the protein cross-linking enzyme is allowed to act on the soy milk obtained by the raw squeezing method or kure before being separated from the soy milk and okara by the raw squeezing method, and then sterilized. Soymilk manufacturing method. The method for producing freshly squeezed soymilk according to claim 2, wherein the sterilization is performed by an indirect sterilization method, a direct steam injection method or a retort method. A soy milk product using the raw squeezed soy milk according to claim 1 as a raw material. 5. The soy milk product according to claim 4, wherein the soy milk product is selected from the group consisting of soy milk, tofu, prepared soy milk, soy milk drink, soft drink, soy milk pudding, soy milk jelly, soy milk soup, tofu pudding, tofu jelly, tofu soup, yuba and sugar beet. Soy milk products.