JPH06209716A - Production of mixed protein crosslinked with soybean casein - Google Patents

Abstract

PURPOSE:To provide an edible protein suitable to be kneaded into fish paste product and animal meat paste product. CONSTITUTION:The objective mixed protein crosslinked with soybean casein is produced by treating an aqueous solution containing soybean protein and casein with a transglutaminase and heating and drying the reaction product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a cross-linked mixture of soybean protein and casein modified by using transglutaminase (hereinafter abbreviated as TGase), which is excellent in kneading into marine products and meat products. It provides one of the proteins.

[0002]

2. Description of the Related Art Conventionally, fish meat such as kamaboko, chikuwa, fried kama, ham and sausage, and meat-paste products (fish paste products and livestock paste products) have been subject to drastic fluctuations in raw material prices, and soybean protein is typical for cost stability. It has been practiced to substitute a part of fish meat and meat with plant protein which is used. However, these vegetable proteins have drawbacks such as poor compatibility with animal proteins particularly in terms of their physical properties and weak physical properties due to addition, and are still of sufficient quality characteristics to substitute for fish meat and livestock meat. Things have not been obtained. In addition, there is a drawback in that it lacks transparency in terms of color tone.

However, the properties required of the soybean protein used for kneading are (1) formation of a gel having a strong gel-forming property and a high elasticity. (2) It has excellent solubility. (3) The formed gel should be transparent. (4) Excellent water retention and water spreading properties. (Five)
Good dispersibility (water wettability). Etc. are mainly given.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to provide a soybean protein which is well compatible with animal protein, that is, the physical properties of the soybean do not deteriorate when added, and the above-mentioned required characteristics can be satisfied. Is to provide.

[0005]

Means for Solving the Problems The present inventor has conducted extensive studies to solve the above problems, and by using casein in combination with soybean protein, in detail, TGase was added to a solution containing soybean protein and casein. A very transparent gel is formed by the action of the soybean, which is rich in elasticity by the addition of soybean protein, has good compatibility with animal protein, and is excellent in solubility. They have found that they can be obtained, and have completed the present invention based on this finding.

That is, the present invention relates to a method for producing a soybean-casein-crosslinked mixed protein, which comprises reacting an aqueous solution containing soybean protein and casein with transglutaminase, followed by heating and drying.

The present invention will be sequentially described below.

As the soybean protein used in the present invention, isolated soybean protein, concentrated soybean protein or an unheated and heated soybean protein-containing aqueous solution which can be obtained in the production process thereof (by dissolving casein in the present invention, An aqueous solution containing soybean protein and casein in the method of 1.) can be prepared, but preferably from the viewpoint of increasing the crude protein content, defatted soybean is extracted with water and the okara component is removed. is there. Further, it is preferable that the material that has been subjected to the heating step once has a stronger effect of TGase. From this point of view, when an unheated soybean protein is used to prepare a mixed aqueous solution with casein, the aqueous solution is once heated in advance to, for example, 50 to 100 ° C. and then cooled to an appropriate temperature, and then TGase is applied. You should let me.

As the casein used in the present invention, milk-derived acid casein, alkali metal casein and the like can be used, which may be heated or unheated.

The ratio of soybean protein to casein in the aqueous solution is 1 to 10 parts by weight with respect to 10 to 50 parts by weight of soybean protein.
The content is in the range of 10 parts by weight, but preferably 1 to 10 parts by weight of the latter to 10 to 20 parts by weight of the former (that is, 1 to 20 parts by weight of soybean protein to 1 part by weight of casein).

The action of TGase on an aqueous solution containing soybean protein and casein means that the protein is crosslinked by utilizing the protein crosslinking ability of TGase. In the present invention, crosslinking between soybean proteins is performed. There are three types of cross-linking, casein and cross-linking between soy protein and casein. Although the characteristics differ depending on each format, the compatibility with animal protein and the transparency of the gel, which are the objects of the present invention, can be achieved in any format or in the case where three formats are mixed. it can. Further, as a result of cross-linking with TGase, the soybean-casein cross-linked mixed protein obtained has a very strong gel-forming property, and thus can be a food material rich in elasticity.

The action of TGase on the aqueous solution containing soybean protein and casein can be carried out specifically as follows.

The protein content (concentration) in the aqueous solution containing soybean protein and casein does not pose any particular problem in view of the properties of the present invention, but it is usually a combination of soybean protein and casein within a range of 5 to 20% by weight of TGase. Is preferable from the viewpoint of operation. Of course, it is not limited to the above range.

The origin of the TGase used in the present invention is not particularly limited. For example, TGase isolated from the liver of guinea pig (hereinafter abbreviated as MTGase), that produced by a microorganism (hereinafter abbreviated as BTGase), Furthermore, natural products, for example, water extracts of vegetables, fruits, etc., and those contained in extracts of fish products such as fish, and washing liquids can be mentioned. MTGase can be prepared, for example, by the method described in JP-A-58-14964, and BTGase can be prepared, for example, in JP-A-1-
It can be manufactured by the method described in No. 27471.

The amount of TGase used is 0.1 to 100 U, preferably 0.2 to 50 U, per 1 g of protein in an aqueous solution containing soybean protein and casein. If the amount used is too small,
The obtained soybean-casein-crosslinked mixed protein lacks transparency and lacks elasticity, while if it is too much, the gel formed becomes brittle and is inferior in compatibility with animal protein.

When an aqueous solution containing soybean protein and casein is added with TGase in the above amount and kept at a temperature of 0 to 80 ° C., preferably 20 to 60 ° C., the enzymatic action of TGase occurs. If the temperature is too low, it will take a long time for the TGase to act properly, and if it is too high, the crosslinking reaction will be too fast and control of the reaction will be difficult, and TGase will be inactivated.

When TGase is allowed to act at such a temperature, 1
Moderate cross-linking occurs in minutes to 5 hours.

The action of TGase on the soybean protein aqueous solution is preceded, and then the casein aqueous solution is added to further add TGase.
ase, on the contrary, the action of TGase is preceded by the casein solution, and then the soybean protein solution is added.
It does not matter how the TGase acts. In this case as well, the action conditions (temperature, time) of TGase and the final ratio of soybean protein and casein are the same as those described above. Either method is included in the embodiment in which transglutaminase is allowed to act on the aqueous solution containing soybean protein and casein referred to in the present invention.

After that, heating is carried out in order to impart functionality such as solubility to the target soybean-casein-crosslinked mixed protein together with sterilization for deactivating TGase and preventing protein spoilage. . For this purpose, the heating temperature is 70-
The temperature is preferably 200 ° C., and is preferably 100 to 150 ° C. from the viewpoint of color tone, odor and gel forming property. When the heating temperature is 70 ° C or lower, the inactivation of TGase is insufficient. If the inactivation of TGase is insufficient, the reaction proceeds further, and a certain quality cannot be obtained, which is not preferable.

The subsequent drying can be performed by an appropriate method such as freeze drying after heat drying. The conditions are not particularly limited, but it is needless to say that conditions such as temperature at which the protein is further denatured should be avoided. From this point of view, it is preferable that the inlet temperature of the dryer is usually 130 to 200 ° C. when spray drying. Of course, freeze-drying can also be used.

The soybean-casein-crosslinked mixed protein thus obtained can be mainly used in fish paste products and livestock paste products.

[0022]

EXAMPLES The present invention will be further described below with reference to examples.

Example 1 (Production of cross-linked soybean casein protein) 9 parts by weight of water was added to defatted soybean (obtained by peeling soybeans from Illinois, USA and then extracting with n-hexane at room temperature) to give a pH of 7. The protein was extracted by stirring at 0 ° C. for 30 minutes at 40 ° C. Okara was removed from the extracted product by a decanter to obtain an extract. The protein in this extract was isoelectrically precipitated (pH 4.5) and whey was removed by a decanter to obtain a protein curd.

Water was added to the curd so that the solid content was 10%, and the pH was adjusted to 7.0 with NaOH to prepare a soybean protein aqueous solution. On the other hand, sodium caseinate (manufactured by New Zealand) was dissolved in water at 40 ° C. so as to have a solid content of 10%, and a sodium caseinate aqueous solution was prepared at pH 7.0. These aqueous solutions were mixed at the ratios shown in Table 1 below, and TGase (specific activity 1000 U per 1 g of protein in the mixed aqueous solution) was mixed.
/ G) 1.5 U each, and add at 50 ° C for 30
It was kept for a minute to act on TGase.

Each sample thus treated with TGase was heated at 120 ° C. for 30 seconds and then spray-dried to obtain a soybean-casein-crosslinked mixed protein (Samples 1 and 2).

For comparison, an aqueous solution of soybean protein and casein was similarly prepared, mixed, and heated and dried in the same manner except that TGase was not added to prepare samples (Samples 3 and 4). ).

A comparison of the properties of these samples is also shown in Table 1.

[0028]

[Table 1] Table 1 Ingredients and evaluation items Sample 1 2 3 4 Soybean protein aqueous solution (parts by weight) 80 95 80 95 Casein aqueous solution (parts by weight) 20 5 20 5 TGase + + − − Solubility 0.93 0.95 0.93 0.91 Gel strength (g) 258 354 152 145 Elasticity (mm) 7.9 8.1 6.6 6.8 Color tone Transparent Somewhat transparent Colored Table 1 shows that according to the method of the present invention, TGase treatment makes gel strength and elasticity excellent and a transparent protein of color tone. It was found that a powder was obtained. In addition, this TGase-treated protein powder has excellent gel strength and therefore excellent water spreading properties.

By the way, the evaluation method of the characteristics in the above table is as follows.
It is as follows.

(1) Solubility 2.5 g of protein powder was dispersed in 100 ml of water, stirred at 5 ° C. for 90 minutes, shaken, and then lightly centrifuged to measure the nitrogen content of the supernatant by the Kjeldahl method ( It is shown in terms of the ratio with the amount of nitrogen in the protein powder.

(2) Gel Properties 350 ml of water was added to 100 g of protein powder, and the mixture was kneaded for 10 minutes by a crusher, and the kneaded product was filled in a casing tube (fold width 47 mm). Then, after heating in hot water at 85 ° C for 50 minutes, it was cooled to room temperature and sliced into 30 mm thick slices with a rheometer manufactured by Fudo Kogyo Co., Ltd.
The strength was measured using a φ plunger.

The strength (g) obtained was taken as gel strength, and the dent (mm) was taken as elasticity.

(3) Color tone The color tone here is a feeling of transparency, which was visually evaluated.

Example 2 (Use of soybean-casein crosslinked mixed protein for sausage) Soybean-casein crosslinked mixed protein (Samples 1 and 2) and soybean casein mixed protein (Samples 3 and 4) obtained in Example 1 and Ground cut pork is mixed and cut at a ratio of 3 parts by weight of the former and 97 parts by weight of the latter, seasoning (a small amount of sodium glutamate) is added and further mixed, packed in a collagen tube, dried at 60 ° C., and smoked, Steam boiling was performed at 75 ° C. to obtain sausages (Samples 1, 2, 3 and 4 respectively).

The results of evaluation of the sausage thus obtained are shown in Table 2 below. The yield was represented by the weight ratio before and after heating, and the water separation was represented by the amount of water separation when pressurized at 1 kg / cm ² for 4 minutes. The texture and the color tone were evaluated by a sensory evaluation of 5 grades from 1 to 5 (the higher the score, the better).

[0036]

[Table 2] As shown in Table 2, the TGase acting system was preferable because it had a higher yield, a smaller water separation, an excellent compatibility with pork, and an appropriate texture as well.

Test Example 1 A comparison of the gel characteristics and other characteristics of the soybean-casein mixed powder prepared by the same method except that the soybean-casein cross-linked mixed protein produced by the method of the present invention and TGase are not allowed to act is given below. It is shown in Table 3. The superior one was considered good.

[0038]

[Table 3] Table 3 Evaluation items Present invention TGase inactive solubility Equivalent gel strength Good Water spreading characteristics Good elasticity Good color tone (transparency) Good From Table 3, the physical properties and color tone of the present invention are clearer ( There was an advantage of transparency.

Incidentally, the method of this inspection will be described in detail. Four kinds of samples were prepared by the same method as in Example 1 (samples corresponding to Samples 1, 2, 3 and 4 in Example 1, respectively, Samples 1a, 2a, 3a and 4a), and sample 1a for each evaluation item
Was compared with Sample 3a, and Sample 2a was compared with Sample 4a.

The results of the two comparisons are exactly the same for each evaluation item. As shown in Table 3, the results of the present invention (Sample 1a and Sample 2a) and TGase inaction (Sample 3) are shown.
a and sample 4a) could be shown together.

[0041]

INDUSTRIAL APPLICABILITY According to the method of the present invention, a soybean-casein-crosslinked mixed protein obtained by allowing TGase to act on an aqueous solution containing soybean protein and casein is well compatible with animal protein and has a transparent elasticity. Since it forms a gel having properties, it exhibits an excellent effect as a protein for kneading products using animal protein represented by meat and fish meat.

Front Page Continuation (72) Inventor Yutaka Nishimura 1-1 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Ajinomoto Co., Inc. Food Research Institute

Claims (4)

[Claims] 1. A method for producing a soybean-casein-crosslinked mixed protein, which comprises reacting an aqueous solution containing soybean protein and casein with transglutaminase, followed by heating and drying. 2. The method for producing a soybean-casein crosslinked mixed protein according to claim 1, wherein the solution containing soybean protein and casein is heated. 3. The soybean protein and casein are added to the former 1 respectively.
The method for producing a soybean casein-crosslinked mixed protein according to claim 1 or 2, wherein the latter is used in a ratio of 1 to 10 parts by weight with respect to 0 to 20 parts by weight. 4. A soybean-casein-crosslinked mixed protein for a fish paste or a livestock paste produced by the method according to claim 1.