JPS6053587B2 - Soy milk production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing soymilk from which soybean odor and bitterness and astringency are removed.

11, especially as a raw material for fermented vegetable protein products such as yogurt, etc. This invention relates to an excellent method for producing soymilk.

In general, soybean protein is nutritionally superior among vegetable proteins, and is inexpensive because it is produced in large quantities, so it is valued as a substitute for or even better than animal protein. It has come to be.

Since ancient times, in Japan, tofu has been manufactured using soybean protein as a raw material, and vegetable protein has been utilized effectively. In recent years, soybean protein has attracted attention as a health food due to its vegetable protein and associated vegetable oil.

Among these, soy milk, which is intended for direct consumption, is not only inexpensive, but also can be used as a substitute for milk that contains animal fats due to its combination with vegetable oils, and is also a healthy drink that prevents the intake of large amounts of animal fats. It is now offered as. However, there were major problems with the production of this soy milk. This is due to the fishy odor of soybeans, or so-called soybean odor, and if this soybean odor is strong, no matter how well seasoned it is, there will be a strong sense of reluctance when drinking it, and it will not be possible to drink it all the time. . Therefore, many inventions have been made to eliminate this soybean odor.

Broadly speaking, there are two methods: one is to remove the soy odor after making soy milk, and the other is to remove the soy odor by processing before making soy milk and then make it into soy milk. However, at present,
The cause of soybean odor is that when lipoxidase in soybeans comes into aerobic contact with oils and fats in soybeans while still active, n-hexanol is produced, and the presence of this is said to cause soybean odor. If soy milk is made without any treatment, n-hexanol will already be produced in the soy milk, and this n-hexanol must be removed. Therefore, it seems more reasonable to treat soybeans themselves to deactivate lipoxidase. Therefore, when looking at the publicly known publications regarding the latter method, the technology can be found in 1. Japanese Patent Application No. 50-40495 (115956.1988) and 2. Japanese Patent Application No. 48-87209 (4263.1988). It will be done. Method 1 involves roasting the soybeans for a short time, soaking them in water together with powdered activated carbon, removing the activated carbon and water, and then grinding them to make soymilk. Method 2 involves soaking the soybeans for about 10 hours. There is a method of boiling the soybeans, grinding them, and making the whole soybean drink as is.

According to methods 1 and 2, the soybean grains are heated considerably, so the deactivation of lipoxidase is sufficiently recognized. This is not a desirable method for producing soymilk, as it involves the use of activated carbon, makes processing complicated, and there is a risk that trace amounts may remain in the soymilk.In addition, method 2 requires boiling for 30 minutes, so the process is complicated. There is a blister odor,
In addition, the entire product is thermally denatured, and even if the entire product is slurried, it no longer becomes soy milk but boiled soybean juice, which is far from the method used to produce soy milk and is therefore undesirable. The present inventors conducted research to completely eliminate the soy odor that is associated with the production of soy milk, and found that most of the lipoxidases were deactivated by short-term heating that did not cause thermal denaturation of soy protein. I knew that I would be forced to do so.

However, if even a small amount of lipoxidase is present, it will come into contact with fats and oils and produce n-hexanal, producing a soybean odor. Therefore, in order to deactivate the lipoxidase that remained, although most of it had been deactivated, hot water of 75°C or higher was used during the next step of grinding the soybean grains. It was discovered that the soybean odor can be completely prevented by deactivating the soybean before it comes into contact with fats and oils. In this way, it was possible to obtain soymilk with the soybean odor removed, but when drinking this, a bitter and astringent taste different from the soybean odor was felt.

This seems to be because the soybean odor, which had previously been largely hidden, has become noticeably more bitter and astringent due to the removal of the soybean odor. Although the true nature of this bitter and astringent taste is still unknown, the present inventors further conducted research to remove this bitter and astringent taste, and found that when soybeans are ground, an aqueous solution containing 0.07% or more of sodium bicarbonate is used. They learned that the presence of liquid can eliminate bitterness and astringency all at once.

By integrating the above findings, the method for producing soymilk of the present invention, which completely eliminates soybean odor and bitterness and astringency, has been completed.
The present invention involves treating whole soybeans, peeled soybeans, or an aqueous soaked product thereof at a temperature of about 80°C or higher for a short period of time to reduce lipoxidase activity without substantially causing thermal denaturation of soybean protein; The soy milk extraction raw material obtained here is 75 to 1
Soybean odor and soybean odor characterized by grinding in the presence of an aqueous solution containing 0.07 to 5.0% sodium hydrogen carbonate at 00°C to obtain a slurry, and optionally separating soybean milk from the obtained slurry. The present invention relates to a method for producing soymilk from which bitterness and astringency have been removed.

The characteristics of the present invention include a step of treating raw soybeans at temperatures of about 80°C or higher for a short period of time, preferably 2 to 5 minutes with hot water, and a step of treating the raw soybeans with hot water at a temperature of 75 to 100°C. ~
The point is that the step of grinding in the presence of an aqueous solution containing 5.0% sodium bicarbonate is continuously combined.

Through this continuous process, we have succeeded in completely deactivating the lipoxidase in soybeans and completely eliminating the bitter and astringent taste. The raw soybeans of the present invention may be either whole soybeans or peeled soybeans, but defatted soybeans are not used.

In addition, whole soybeans and peeled soybeans soaked in water can be used similarly. As the first step of the present invention, these soybean raw materials are heated to about J8O<0>C or higher.

Heating may be done by boiling in an aqueous medium or by spraying steam, and the key is to increase the temperature of the soybeans and deactivate lipoxidase. However, it is desirable to carry out this heat treatment in as short a time as possible so as not to reduce the extraction rate of soluble protein in the subsequent extraction step.

Generally, about 2 to 2 powders are heated at about 80°C or higher, preferably about 2 to 1 powder is heated at about 90°C or higher, and most preferably about 2 to 10 minutes in boiling water. This is done by heating. On the other hand, even when soybeans are placed in hot water of about 80° C. or lower, it is sufficient to satisfy the above heating conditions within a few minutes.

Next, since the solid content of soybean milk extracted varies depending on the heating conditions, the hardness of the various treated soybeans, the solid content of recovered soymilk, and the presence or absence of soybean odor were measured.

The results are shown in Table 1. Hardness was measured using a rheolometer (manufactured by Iio Denki) using a 5k9 pressure sensitive part, chart speed 150cmImin1 plunger speed 12
The cmImin 1 blade type was measured using a wedge type, the clearance was set to 2, and the hardness value was determined and measured as the average value of 10 treated soybeans per grain. In the soybean milk preparation method, raw soybean 1k9 was heated (changed) and ground in the presence of water to obtain a 10k9 grinding liquid, which was passed through a 200 mesh sieve to obtain soymilk. This soymilk was measured for solid content and presence or absence of soybean odor. From the results in Table 1,
From the recovered soymilk solid content and the presence or absence of soybean odor, it can be seen that the heat treatment conditions are preferable so that the hardness of the heat-treated soybeans falls within the range of about 1.7 to 3.0 kg.

The heated aqueous medium in this first step may be tap water, soft water, or a slightly alkaline solution such as sodium bicarbonate, caustic soda, or caustic potash.

Slightly alkaline solutions are preferred because they increase the solids extracted from soy protein into soy milk. Table 2 shows the solid content recovered when whole soybeans were boiled for 5 minutes in tap water and sodium bicarbonate solution (concentration changes) as heated aqueous media.
The method for preparing soy milk is to boil 1 kg of whole soybeans for 5 minutes, grind them in the presence of water, adjust the grinding liquid to 10k9,
Soy milk was obtained by filtration through a mesh sieve. From the results in this table, it can be seen that an approximately 1% sodium bicarbonate solution exhibits a good recovery rate as the heating medium, that is, the boiling liquid composition in this step.

In the present invention, as a second step, the heat-treated raw soybeans obtained here are subjected to soymilk extraction treatment.

The extraction process may be performed using any of the stone mills, mechanized grinders, etc. that have been used for a long time, but in the present invention, the presence of an aqueous solution containing 0.07 to 5.0% sodium hydrogen carbonate at 75 to 100°C is used. It takes place below. This 0.07~J
5. The aqueous solution containing 0% sodium bicarbonate may be a freshly prepared aqueous sodium bicarbonate solution, or may be a boiled solution of the sodium bicarbonate solution used to heat the soybeans in the first step. A 0.07-5.0% sodium bicarbonate solution can remove the bitter and astringent taste of soybeans, and heating at 75-100°C can completely deactivate the slight remaining lipoxidase. This is an extremely important process for achieving this goal.

The presence of the aqueous solution containing sodium hydrogen carbonate is achieved by putting it into a grinder together with the raw soybeans, or by pouring this aqueous solution into the place where the soybeans are being ground.

The grinding in this step is carried out using a conventional grinder such as a micro-refiner wet pin mill, a vertical grinder, a Ritz mill, or a homomixer.

The amount of water added in this grinding process is adjusted according to the desired level of the solid content in the resulting soybean grinding liquid or the soybean milk solid content obtained in the subsequent process, and the amount of the obtained soybean grinding liquid is twice the amount of soybeans used as the raw material. It is preferable that the weight is as follows. Next, the presence or absence of bitterness and astringency was tested by changing the grinding liquid components, and the results are shown in Table 3.

This table shows that aqueous solutions containing 0.1%, 0.2%, and 1% sodium bicarbonate are preferable for removing bitter and astringent taste;
．． It can be seen that bitter and astringent taste removal is not achieved with 0.05% caustic soda solution. In the present invention, a ground soybean slurry is obtained through the above steps, and soybean milk is separated from the slurry. The soybean milk separation step can be carried out immediately as it is by sieving or the like, but it is preferable to homogenize it under a pressure of 0 to 1400 PS1 in order to more effectively elute the soluble components. This homogenization is performed using a pressure homogenizer at 0 to 1400 PS.
The extraction rate of soluble protein is thereby further increased. However, 1400
Powerful homogenization by applying pressure of PS1 or higher will make the lees finer and bring them into the soymilk, unnecessarily increasing the roughness and lowering the quality of the soymilk! I don't like it because I have to go down. The slurry was then passed through a homogenizer under each pressure and
The Oki liquid was filtered through a mesh sieve and its protein content was examined.

The results are shown in Table 4 below. From this table, it can be seen that the protein content of the liquid that passed through the 200 mesh sieve rapidly increased due to the homogenization of the pressure exceeding 0 to 1400 pSi, and that lees was mixed into the liquid.

This was tested for sensory evaluation and protein stability, and the results were as shown in Table 5 below. As is clear from this table, it is found that the appropriate pressure for homogenization is 0 to 1400 pSi.

The thus homogenized slurry is then preferably heated to 80° C. or higher. This heating at 80°C or higher improves the filtration performance for lees separation and at the same time improves the filtration performance of lees separation. It is useful to improve the extraction efficiency of soybean milk and increase the content of soluble protein in soybean milk. Next, the homogenized slurry is
The soybean milk was heated to 0°C and passed through a 200 mesh sieve to measure the solid content and lees content of the soymilk.

The results are shown in Table 6 below. As is clear from this table, the soybean milk solid content increases rapidly and the lees content decreases from 80°C. This heating is appropriately performed using a heating tank, a plate heater, or the like. The preferred temperature for extraction of soluble proteins is about 80° C. or higher, which increases the solid content in soymilk and at the same time makes the subsequent sieving step extremely easy. The slurry obtained here or the heated slurry is separated from the lees.

In this separation step, the lees are removed using ordinary machines such as a filter breath, decanter, centrifuge, and vibrating sieve to obtain smooth purified soymilk. Thus, the soymilk obtained by the present invention retains the unique flavor of soybeans, but has no soybean odor, no bitter or astringent taste, and is almost tasteless and odorless, making it superior to vegetable protein drinks and other protein products. It has the optimum quality as a raw material.

Next, test examples of the present invention will be shown.

Test Example 1 Peeled soybeans were placed in a boiling 1% sodium bicarbonate solution and heated for 1 to 5 minutes (variable), and each treated soybean was poured with cold water or 80°C hot water during grinding. The resulting slurry was subjected to a sensory test at the same time as the n-hexanal content was measured.

The results are shown in Table 7 below. As is clear from this table, in the case of dehulled soybeans, if the second step is 80°C hot water pouring and grinding, 2 minutes of heating in the first step is sufficient.

Test Example 2 Whole soybeans were placed in a boiling 1% sodium bicarbonate solution and heated for 3 cases, 5 and 1. Also, the soybeans soaked in water for 5 hours were heated for 30 minutes, and a control sample was prepared. The odor and taste of the same treated but unheated products were sensory tested.

The results are shown in Table 8 below. Ru.

Test Example 3 100 kg of peeled soybeans were poured into a boiling 1% sodium bicarbonate aqueous solution, boiled for 3 minutes, and the resulting heated soybeans were ground while pouring a 0.1% sodium bicarbonate aqueous solution at 90°C. A slurry with a 10% soybean content was obtained, which was passed through a homogenizer at 1400 pSi and sieved through a 200 mesh screen.The resulting soymilk was centrifuged at 3000 rpm for 15 minutes, and the amount of protein in the supernatant was measured.

As a control, 100k9 of peeled soybeans were similarly boiled in the same solution for 3 times, and the resulting completely dehulled soybeans were directly heated to 42 kg.
Homogenized at 80 pSi and then heated to 3000 r'Pm
The mixture was centrifuged for 5 minutes, and the amount of protein in the supernatant was measured.

These results are shown in Table 9 below.

As is clear from this table, the sedimentation rate of the protein boiled for 3 minutes is faster than that of the protein boiled for 3 minutes, indicating that the protein is thermally denatured and becomes insoluble.

On the other hand, the sample boiled for 3 minutes has a stronger water affinity because it is dissolved by soluble protein and then thermally denatured. The present invention will be explained below using examples.

Example 1 2.5k9 whole soybeans were put into a boiling 1% sodium bicarbonate aqueous solution 20e and heated for 6 minutes.

The resulting heat-treated soybeans of 3.5k9 exhibited a hardness of approximately 2.25k9 in a rheometer. A 0.1% aqueous sodium bicarbonate solution heated to 90°C or higher was poured into the heat-treated soybeans and ground, and the final volume was used. The amount was 20k9, which is 8 times the amount of soybeans for commercial use. 20k9 of soybean grinding liquid was heated to 80°C and the lees was separated using a 200 mesh vibrating sieve to obtain 12k9 of soybean milk with a total solid content of 9.5% and a pH of 7.4.

Example 2 2.5k9 whole soybeans were put into a 1% aqueous sodium bicarbonate solution 20e heated to about 80°C and heated rapidly to boil, then heated for 5 minutes.

The obtained heat-treated soybean has a rheolometer rating of approximately 2.0k.
It showed a hardness of 9. This heat-treated soybean weighed 3.6 kg, and was treated in the same manner as in Example 1 to achieve a total solid content of 9.5%.
12 kg of soy milk with a pH of 7.4 was obtained. Example 3 Soybean milk 12k9 was obtained by completely utilizing the waste liquid of the broth by carrying out the same process as in Example 1 except that the broth was used instead of the 0.1% sodium bicarbonate solution.

With a total solid content of 10% PH&3, the degree of coloration was higher than in Examples 1 and 2, but as in Examples 1 and 2, no soybean odor or bitter or astringent taste was observed. Example 4 Example 1
, 0 to about 300 kgI of the soybean grinding liquid obtained in steps 2 and 3.
The soybean milk was passed through a homogenizer under a pressure of cf1 to turn the insoluble solids into fine particles, and passed through each mesh sieve to obtain soymilk containing a large amount of lees.

When a homogenizer is used, the particles of lees that are discharged are finer and can be reused for snacks, etc. The obtained soymilk has a slightly grainier feel compared to refined soymilk, but has no soybean odor or bitter or astringent taste.
Furthermore, if it is made into a drink as in Reference Example 1, the graininess will hardly be a problem. The table shows the lees content (% by weight) in soymilk in relation to the mesh of the sieve and the pressure of the homogenizer. Example 5 The pH of the soybean grinding solution prepared by the method of Example 1 was adjusted with hydrochloric acid or an organic acid, and acid precipitation was performed in a conventional manner to recover fat-containing acid-precipitated proteins.

Add alkaline solution to this collected sediment to make it 6.8~7.
0 to obtain fat-containing high protein soymilk. This soymilk had a whiter color tone than the soymilk of Example 1, and had no soybean odor or bitter or astringent taste. If this soymilk is spray-dried, a high-protein soymilk powder without soybean odor or bitter or astringent taste can be obtained.

Example 6 The soy milk of Example 1 was mixed with 78.3%, sugar 1%, and glucose 0.
Seasoned with 5% vegetable oil, 2.3% vegetable oil, 0.1% salt, and 17.8% water, and adjusted the pH to 6.8 with hydrochloric acid or organic acid.
After adjusting to homogeneity, heat sterilization and filling were performed to obtain a soy milk beverage.

This soy milk drink has the same composition as milk, and has no soy odor or bitter or astringent taste. Example 7 60% soy milk from Example 1, 9.3% sugar, 1 cocoa powder
．． 34%, salt 0.18%, and water 29.18%, and was commercialized by the method of Example 4 to obtain a cocoa-containing soymilk beverage.

This beverage has a pleasant cocoa flavor and is completely free from soybean odor and bitter and astringent taste. Example 8 The soy milk obtained in Examples 1, 2, and 3 whose pH was adjusted to 6.8 to 7.0 with hydrochloric acid or an organic acid, or the soy milk drink obtained in Examples 4 and 5 was sprayed in a conventional manner. A powder was obtained by drying.

These soy milk powders and soy milk beverage powders had no unpleasant soy odor or bitter or astringent taste even when they were in powder form or when they were reduced to liquid form by adding water.

Claims (1)

[Claims] 1 Whole soybeans, peeled soybeans, or aqueous soaked products thereof are treated for a short period of time at about 80°C or higher, thereby activating lipoxidase activity without substantially causing thermal denaturation of soybean protein. The soy milk extraction raw material obtained here is heated to 75-100℃.
Soybean odor and bitter astringency characterized by grinding in the presence of an aqueous solution containing 0.07 to 5.0% sodium bicarbonate to obtain a slurry, and optionally separating soymilk from the obtained slurry. A method for producing soymilk from which . 2 Whole soybeans, peeled soybeans, or their aqueous soaked products are treated for a short period of time at about 80°C or higher to reduce lipoxidase activity without substantially causing thermal denaturation of soybean protein, thereby producing the obtained product. Soy milk extraction raw material is heated to 75-100℃
of 0.07 to 5.0% sodium bicarbonate to obtain a slurry.
Homogenize under a pressure of ~1400 psi and reduce the homogenized liquid to ca.
A method for producing soymilk from which soybean odor and bitterness and astringency are removed, which comprises heating the soybean to 0° C. or higher and separating the lees using a 200-300 mesh sieve.