JPS60199349A - Preparation of protein - Google Patents

Abstract

PURPOSE:To prepare a protein having excellent taste and flavor, and extremely low oil seed smell, by extracting pressed oil seed with an organic solvent under specific condition, and removing the solvent from the product to effect the deodoization. CONSTITUTION:An oil seed such as soybean is pressed at a water-content of <=10%, and extracted with an organic solvent such as hexane/etchanol, etc. at <=70 deg.C. The residual organic solvent is removed from the extracted oil seed at a temperature above the boiling point of said organic solvent. The obtained solvent-free pressed oil seed is extracted with water preferably having a pH excluding the region near the isoelectric point of the protein. The objective protein can be extracted by this procedure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a protein with very little oilseed odor and excellent flavor.

(Prior art) Soybean protein, which is one of the oilseed proteins, is an excellent vegetable protein but has a unique flavor (commonly known as soybean odor).
Therefore, its use in food and its amount are limited.

Many researchers are continuing to conduct research to solve this problem, and the amount of research is enormous.

The ideas can be roughly divided into ta+investigate the cause of soybean odor and eliminate it, tb+remove the soybean odor (C
) masking to make it undetectable, etc.

Specific methods include: ■ Physicochemical means of inactivating enzymes involved in soybean odor generation such as lipoxygenase through heat treatment; ■ Chemical means using sodium carbonate, etc.; ■ Microorganisms such as lactic acid bacteria and yeast. Examples include biological means utilizing, (2) biochemical means utilizing enzymes such as aldehyde dehydrogenase, and (2) combinations thereof.

However, to date, odorless soybean protein has not been obtained. This is because the mechanism by which soybean odor is generated is complex, soybean odor is not a single component but a compound odor and its substance cannot be clearly grasped, and soybean odor is removed due to the complex higher-order structure of soybean protein. This is due to the fact that it is extremely difficult.

For example, in Japanese Patent Application Laid-Open No. 52-120149 "F Soybean Acid Extracted Protein and Method for Producing the Same,"
1,6-3.5) and NSI (Nitr
A method of neutralizing under severe conditions has been disclosed based on the relationship of (ogenSolble Index). However, even in this case, lipoxygenase is not inactivated, and the problem of soybean odor remains.

The present inventor was acutely aware of how difficult it was to deodorize soybean protein without losing its physical properties, and unfortunately, it was discovered that a sufficiently satisfactory soybean protein was obtained. I couldn't get it. However, after much trial and error, we first eliminated the causes of soybean odor in the soybean raw material and used compressed soybeans that removed as much of the soybean odor as possible, which could still occur during the soybean protein extraction process. By suppressing the generation of certain soybean odor as much as possible, we were able to obtain soybean protein with extremely less soybean odor compared to conventional products.

(Purpose) The present inventor has aimed to obtain a protein with excellent flavor that has very little oilseed ingredients, and has made a soybean protein that has very little soy odor and has an excellent flavor using soybean, which is one of the oilseeds. I considered getting it.

Soybean protein is usually obtained through the following steps.

Soybeans - (pressing) = (defatting) - defatted soybeans (water extraction) - (
In order to achieve the objective, the inventors first of all As a result of research aimed at checking and preventing the production of soy odor,
Mainly ■ Soybean - (pressing) stage and ■ Defatted soybean = (water extraction)
We discovered that a soybean odor occurs during the process, and in order to prevent stains, we need to keep the soybean moisture at a low level during pressing, and if necessary, press at a low temperature. It has been found that the process can be carried out outside the working pH range.

However, I realized that no matter how much I tried to prevent soy odor, there was a limit. As a result of further research, it was discovered that soybeans themselves originally have a certain degree of soybean odor.

Therefore, the present inventors secondly investigated (deodorization).

As a result, by performing extraction with an organic solvent and desolvation under certain conditions in the (pressing) = (defatting) process, it is possible to not only remove the soy odor that the soybean itself originally has, but also to generate soy odor. We have obtained knowledge that can prevent the cause.

By organically combining the above knowledge, we were able to largely eliminate soybean odor, which was a limitation with conventional single or combined processes. Furthermore, this knowledge has led to the completion of the present invention, which can be applied to a wide range of oilseeds including soybeans.

(Structure) The present invention comprises (1) a first step of compressing oil in +i seeds with a moisture content of 10% or less; a second step of extracting the compressed oil seeds at a temperature of 70° C. or lower using an organic solvent; The third step is to remove residual organic solvent from the extracted pressed oil seeds at a temperature higher than the boiling point of the organic solvent. This is a method for producing a protein characterized by including a fourth step of extracting the protein.

Oilseeds include soybean, rapeseed, cottonseed, peanut, sesame, sunflower,
Preferably, those whose protein can be used as food, such as corn.
Soybeans are preferred because of their characteristics, availability, and economy. Below, oilseeds will be explained using soybeans as an example.

Known types of soybeans can be used, and although they may be peeled, it is preferable that the soybean structure is intact. This is because the destruction of the tissue causes enzymes and the like to act, causing soybean odor.

When compressing, the moisture content of soybeans is 10% or less, preferably 5%.
The following are appropriate. When the soybean is compressed by more than 10%, enzymes in the soybean tissue are likely to act on the soybean, and a soybean odor is likely to occur. The moisture content can be reduced using known drying means, with hot air drying being preferred. Moreover, if necessary, it is preferable to press at a low temperature. Preferably below lightning temperature, particularly preferably 0°C
The following are appropriate.

The solvent-soluble components of the pressed soybean can be extracted using a known organic solvent or a mixture of these organic solvents. The extraction temperature is preferably below a temperature at which soybean protein is difficult to denature, that is, below 70°C. Examples of the organic solvent include alcohols such as ethyl alcohol, ketones such as acetone, and ethers such as ethyl ether. Polar solvents such as acetone and ethanol are preferred because they have not only a deodorizing effect but also a decolorizing effect. Particularly preferred is a mixture of a non-polar solvent/polar solvent represented by hexane/ethanol etc., which has the strongest deodorizing effect. A known extraction method can be used. The deodorizing effect of compressed soybeans after solvent removal (60°C) is illustrated in the following table.

In addition, the smell and flavor of soybeans were sensory tested by 40 trained panelists, and the results showed that there was no soybean smell at all...0~
5. I don't really notice a soybean odor... 6-15, I feel a slight soybean odor... 16-25, I notice a soybean odor...
26-35, strong soybean odor...Evaluated as 36 or higher, and arithmetic averaged excluding the upper and lower limits. The same applies below.

Hexane 39 Acetone 33 Ethanol 38 Ether 25 Hexane/ethanol (2/1) 23 After organic solvent extraction, the 831 solvent is removed by filtration, etc., and the remaining organic solvent is heated to a temperature higher than the boiling point of the organic solvent using steam or the like. The solvent can be removed with

It has been said that it is preferable not to raise the temperature at this time, as it greatly affects the denaturation of soybean protein. In the present invention,
The temperature is suitably 63 to 95°C, preferably 68°C.
Above, a temperature of 78° C. or higher is particularly preferred. The higher the temperature, the more pronounced the deodorizing effect is, which is preferable; however, if the temperature exceeds 95°C, the protein will be significantly denatured, depending on the desolvation time, and the yield of the protein extraction in the fourth step will decrease, which is not preferable. There are two methods for removing the solvent, one using dry steam and the other using saturated steam, but the latter method has a greater deodorizing effect. The following table illustrates the deodorizing effect depending on the solvent removal temperature (ambient temperature) after extracting compressed soybeans using n-hexane.

Table-2 Solvent removal temperature: Soybean odor from solvent-free pressed soybeans 60℃ 39 65℃ 29 70’C21 75℃ 13 80’C10 90℃ 9 100℃ 5 When the temperature was 70°C or lower, the pressure was appropriately reduced.

Soybean protein can be extracted with water using compressed soybeans that have been subjected to solvent removal. However, the area near the isoelectric point of soybean protein is pl+3.
6 to 5.4 is not preferable because not only the protein extraction efficiency decreases but also the soybean odor becomes strong. Therefore, the neutral range or pl+
3.5 or less is preferable. If the pH is too low, a large amount of acid will be used to neutralize the isolated soybean protein solution after extraction, resulting in a large amount of salt produced, which will limit the uses of the resulting protein.

The following table shows the degree of soybean odor for each extraction in the ρ1 range.

The effect of desolvation temperature is significant. This is thought to be due to the fact that the desolvent temperature also acts to deactivate enzymes and the like, which, combined with the deodorizing effect, was effective in reducing soybean odor.

Table-3 0,67279 1,03147 1,58146 3,3147 3,43158 4,53617 6,, II 2G 13 7.0 25 12 As explained above using soybean as an example of oilseed,
(11 The first step of compressing oilseeds with a moisture content of 10% or less,
A second step of extracting the compressed part i1 seeds using an organic solvent at 70°C or lower, removing residual ta solvent from the compressed oil seeds after organic solvent extraction at a temperature above the boiling point of the organic solvent. By organically combining the third step and the fourth step of extracting protein from solvent-free and pressed oil seeds in an aqueous system (preferably excluding the area near the isoelectric point), it is possible to It has now become possible to obtain protein with excellent flavor and with very little amount of unobtainable oilseed ingredients.
(Example) Embodiments of the present invention will be described below with reference to Examples.

Example 1 Soybean (produced in Illinois, USA) (moisture 7%) was pressed into flakes to a thickness of about 2 ml, and n-hexane was added 10 times (-/
Extract the solvent at 50°C using the same amount as
/-gauge pressure)) at an ambient temperature of 75° C. to remove the solvent and obtain degreased flakes. To 10 parts of the defatted flakes, 100 parts of water whose pi was adjusted to be acidic was added, and after water extraction, okara was removed to obtain soybean milk. In addition, pl+ during water extraction
were as shown in Table 3 on page 11. Next, the pH was adjusted to 4.5 using hydrochloric acid, whey was removed, and the mixture was neutralized using sodium hydroxide to obtain a protein solution. However, pl+4
．． Since it was difficult to extract with 5, we first removed the whey using pl (4°5) and then neutralized it to remove okara to obtain a protein solution. Each protein solution was spray dried to obtain isolated soybean protein. .

4 trained on the 10% aqueous solution of isolated soy protein.
A sensory test of smell and flavor was carried out by 0 panelists: No soy odor at all...O~5: Almost no soy odor...6~15: Slight soy odor...・16～
25, I feel a soybean odor...26-35, I feel a strong soybean odor...Evaluated as 36 or higher, and the arithmetic average was calculated excluding the upper and lower limits. The same applies below.

Similarly, the desolventizer atmosphere temperature was set to 60°C.
The isolated soybean protein obtained by removing the solvent was also subjected to the same sensory test.

The results are shown in Table 3 on page 11.

The isolated soybean protein obtained by removing the solvent at 75°C had an extremely good flavor with almost no soybean odor.

Example 2 Soybeans (produced in Illinois, USA) were dried with hot air, the moisture content was adjusted to 3%, and the flakes were pressed to a thickness of about 2 mm. N-hexane/98% ethanol = 20/10 (V/V) was prepared. 1
After solvent extraction at 50°C using 0x (W/W) M, the solvent was filtered and the remaining solvent was removed using a desolventizer (steam (4 kg/-gauge pressure)) at an ambient temperature of 75°C.
℃ and the solvent was removed to obtain defatted flakes. 100 parts of water was added to 10 parts of the defatted flakes, and protein was extracted under neutral conditions in the same manner as in Example 1 to obtain isolated soybean protein. As a result of the sensory test in the same manner as in Example 1, the evaluation value was 8, indicating that the flavor was extremely good.

(Effects) As detailed above, the method of the present invention can be widely applied to oilseeds (soybeans, rapeseed, cottonseed, peanuts, sesame, sunflowers, corn, etc.), and is extremely useful for oilseeds. It provides protein with excellent flavor. In addition, in the present invention, the intermediate solvent extraction product (solvent removed) can also be obtained with excellent flavor. These flavorful proteins or intermediate solvent extraction products (solvent removed) greatly contribute to the expansion of their use and quantity as food materials.

Procedural formalities (spontaneous) 1. Case description Patent application dated March 21, 1980 (A) 3, person making the amendment 4, agent 1-32-12 Higashi Mikuni, Yodoyou-ku, Osaka (■532) 5
,? Number of inventions increases due to di positive None 6,'sNi
Positive target specification page 12, line 12 [...steam (4kg/cal
Gauge pressure)) is used..." instead of "...steam (4
kg/cnl gauge pressure) was adjusted and used...
・” I corrected it.

Page 14 of the specification, line 3, ``...steam (4kg/ad cage pressure)...'' was replaced with ``...steam (4kg/ad cage pressure)...''
/c+a gauge pressure) was 8111 and used)...
・” I corrected it.

Claims (4)

[Claims] (1) The first step of compressing oilseeds with a moisture content of 10% or less,
A second step of extracting the compressed oil seeds using an organic solvent at a temperature of 70°C or lower, removing the remaining organic solvent from the compressed oil seeds after extraction with the organic solvent at a temperature equal to or higher than the boiling point of the ta-containing solvent. A method for producing protein, comprising a third step, and a fourth step of extracting protein from solvent-free and pressed oil seeds in an aqueous system (preferably excluding the vicinity of the iso-point). (2) Claim No. (1) in which the oil iM seeds are soybeans.
Manufacturing method described in section. (3) The manufacturing method according to claim (1) or (2), wherein the temperature above the boiling point of the organic solvent is 70° C. or higher. (4) The manufacturing method according to claim (2) or (3), wherein the isoelectric point has a PII of 3.6 to 5.4.