JPH0975007A - Soy protein and gel food - Google Patents

Abstract

(57) [PROBLEMS] To provide a novel soybean protein having physical properties of heat gel obtained by fractionation from defatted soybean, and a gel-like food product using the soybean protein. SOLUTION: Pre-heated in a water system to denature 7
Soy protein containing 60% or more of S globulin (β-conglycinin), and gel foods such as semi-cooked frozen foods and livestock and marine foods containing this soy protein and salt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel soybean protein and a salted gel food, and more particularly to a novel soybean protein capable of imparting a crisp texture and a gel food using the same as a raw material. It is a thing.

[0002]

BACKGROUND OF THE INVENTION Soybeans contain about 35 nutritionally good proteins.
%, The protein has various functionalities such as water retention, water absorption, adhesiveness, emulsifying property, gel forming property, foaming property, film forming property, etc. It is used in various food products as isolated soybean protein.

[0003] Among them, particularly when it is intended to be used for foods that require gel-forming property, the texture is not crisp and sticky, so there is a limitation in use.

On the other hand, it is well known that the main component of soybean protein is a mixture of 11S globulin (glycinin) and 7S globulin (β-conglycinin), and many studies have been conducted on the properties of each. (Kyoko Saio, etc. by "Soybean and its processing")

However, although these studies are academically interesting findings, they are all unheated 11S globulin and 7S globulin.
It was for S globulin.

[0006] Recently, the effect of preheating on the gel-forming ability of various proteins has been reported, which is also egg white (J. Agri. Food. Chem., Vol. 3).
8, No1, Page 32-37, 1990), milk whey (BBBB, Vol. 59, No5, Page83)
4 to 840, 1995), SPI (Journal of Japanese Food Industry, Vol. 28, No8, Page 451 to 456.
1981), and 11S globulin and 7S globulin, which are the main components of soybean protein, have not been known.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a soybean protein which has a crisp texture and is not sticky when the soybean protein is used in a food requiring gel forming property. .

[0008]

That is, one of the inventions is as follows.
It is a soy protein containing 60% by weight or more of 7S globulin (β-conglycinin) preheated in an aqueous system.

Further, the present invention is a gel food containing a soy protein containing 60% by weight or more of 7S globulin (β-conglycinin) preheated in a salt and water system.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors fractionated 11S globulin and 7S globulin, which are the main components of soybean protein,
In various studies on the effect of preheating on gel-forming property of each, the gel containing 7S globulin-rich fraction (preferably 85% or more) forms a crisp texture gel in the presence of salt. It was found that it is suitable for food products.

Among the conventional soybean proteins, 11 globulin was considered to have a greater effect on gel than 7S globulin (Jounal of Texture Studies, 9 (1978) 1
35-157). According to the research results of the present inventor, although the strength at which the gel breaks is certainly higher for 11 globulin, the load (g) value for the same deformation (mm) in the initial stage of deformation is larger (Fig. 1), this is crisp,
It is considered to be a factor of getting caught up. On the other hand, 7S globulin is smaller in the above-mentioned value, so that a gel with a crisp texture can be formed. That is, the ratio until the fracture (load ÷
It can be said that the larger the deformation, the better the crispness and the less stickiness, and that it is suitable for gel foods.

The content of 7S globulin is about 25 to 35% by weight in ordinary soybean protein isolates, but it should be 60% by weight or more (preferably 85% by weight or more) by fractionation. As a result, soybean protein suitable for the gel food is obtained.

The 7S globulin fractionation method is as follows:
The method of Thanh et al. (J. Agr. Food. Che.
m. , (1986) 24.1117) or the method of Hirotsuka et al. (JP-A 61-23679). The method of Nagano et al. (JP-A-5-43597) is preferable because it can easily fractionate 7S globulin with high purity, but of course it is not limited to these fractionation methods.

The preheating condition is such that there is a thermal history such that 7S globulin is denatured in order to increase the gelling power, and it can be passed through an instantaneous sterilizer such as VTIS.
It is heated for about 60 seconds to several seconds (preferably 30 seconds to several seconds) by high temperature steam of 0 to 150 ° C (preferably 130 ° C to 150 ° C). The denaturation of 7S globulin can be confirmed by a decrease in the enthalpy of the endothermic peak measured by the differential scanning calorimeter and a decrease in the absorption of the amide I band measured by the infrared absorption meter.

The gelled food is not particularly limited. For example, half-cooked frozen foods (hamburgers, meat dumplings, maimai, gratin, teriyaki chicken, minced pork cutlets, beef cutlets, etc.) and marine products (hams, sausages, wieners, grilled pork, bacon, kamaboko, chikuwa, satsumaage, hanpen, etc.) Can be mentioned.

Salt is essential for the gel food containing 7S globulin soybean protein, and preferably 0.5 wt% or more is contained in the gel food.

Examples of the salt include alkali metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as calcium salt and magnesium salt, and ammonium salt. Particularly, sodium and potassium monovalent alkali metal salts are preferable in terms of flavor.

[0018]

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the scope of the present invention is not limited to these examples. In addition, the part and% shown in an example mean a basis of weight.

Example 1 15 parts of water was added to 1 part of defatted soybean (crude protein: 46.2%, NSI: 87), and the mixture was stirred at room temperature at low speed with a homomixer, and the pH was adjusted to 7 with a 20% sodium hydroxide solution. Extraction was carried out for 30 minutes while maintaining at 0.5. Then, the extract was filtered with a filter cloth and then centrifuged at 9200 G for 20 minutes to remove insoluble matter.

To the extract (soy milk) thus obtained, 1
Sodium bisulfite (SO ₂ content of 60-69% is 0.98 per 1 liter of soy milk)
g) was added and the pH was adjusted to 6.4 with 20% hydrochloric acid,
The 11S protein fraction was separated by allowing the precipitated protein fraction to stand in ice water overnight and centrifuging at 6760 G for 20 minutes.

Next, sodium chloride was added so that the obtained supernatant was a 0.25 M solution (that is, ionic strength 0.25), and the pH was adjusted to 5.0 with 20% hydrochloric acid. After the adjustment, the mixture was allowed to stand at 4 ° C. for 30 minutes and then centrifuged at 6760 G for 20 minutes to separate the insoluble portion. afterwards,
Dilute the supernatant twice with cold water to obtain an ionic strength of 0.125, p
The 7S protein fraction was obtained by adjusting to H4.8 and centrifuging at 6760 G for 20 minutes. The purity of this 7S protein fraction was 90% as determined by the area ratio by densitometry of the pattern obtained by SDS-polyacrylamide gel electrophoresis.

Next, the 7S protein fraction was neutralized with NaOH, and the product having a protein concentration of 10% was subjected to a plate type continuous sterilizer (VTIS of Alfa Laval Co.) at 140 ° C. for 15 minutes.
After heat sterilization for 2 seconds, isolated soybean protein rich in 7S globulin (referred to as 7S-SPI) was obtained.

SPIs having different 7S-SPI contents were prepared and heated gels were prepared under the conditions of protein concentration 16% and salt concentration 2.5%. The gel has a diameter of 20 mm and a height of 20 mm
It was formed by heating at 80 ° C. for 30 minutes in the mold. The physical properties of the gel were measured with Leoner (manufactured by Yamaden Co., Ltd.). The jig is a 3mm diameter rod with a 5mm diameter fluorinated resin sphere attached to it, 300mm / m
The puncture test was performed at a speed of in. The results are shown in Table 1 below. The texture evaluation was performed according to the following criteria. (Good crispness, no stickiness) +++: Very good ---: Very poor ++: Very good ---: Very poor +: Somewhat good-: Somewhat poor ±: Control (equivalent to commercially available SPI)

[0024]

[Table 1] Table 1 ───────────────────────────────── 7S content% 90 75 75 60 45 30 ─── ────────────────────────────── (A) Breaking load g 401 402 401 405 408 (B) Breaking deformation mm 12.1 12.5 13.0 13.5 14.1 (A) ÷ (B) 33.14 32.16 31.07 30.00 28.93 Texture ＋＋＋＋＋＋＋ ～ ＋＋ ± ──────────────────────────── As is clear from the results shown in Table 1 above, the value of (A ÷ B) increases as the content of 7S increases, which is sensually crisp, It shows that it becomes a non-sticky gel.

Example 2 S obtained in the same manner as in Example 1 described above, containing 7% S and 85% S
The same procedure was performed except that PI was prepared and the salt concentration was changed. The results are shown in Table 2 below.

[0026]

[Table 2] Table 2 ───────────────────────────────── Salt concentration% 0 0.05 0.5 1.5 2.5 ─ ──────────────────────────────── (A) Break load g 502 495 404 403 404 (B) Break deformation mm 18.1 17.1 12.4 12.2 12.3 (A) ÷ (B) 27.73 28.94 32.58 33.03 32.80 Texture −−− ＋++＋＋＋＋＋＋＋ ────────────────────────── ─────── As is clear from the results shown in Table 2 above, the addition of a small amount of salt increases the value of (A ÷ B), which is sensually crisp. It often shows that the gel does not stick.

Example 3 and Comparative Example 1 Sausage dough having the following composition was folded by a conventional method to a folding diameter of 48 m.
It is packed in a vinyl chloride casing with a core temperature of 7
It was manufactured by heating to 2 ° C.

────────────────────────────── Example 3 Comparative Example 1 ──────────── ──────────────────── Pork red meat 52 parts 52 parts pork fat 25 25 ice 21 21 7 SPI with 85% 85% FUJIPRO SE (Fuji Oil Co., Ltd.) ─ 2 Salt 1.4 1.4 Polymerized phosphate 0.4 0.4 Na nitrite 0.01 0.01 MSG 0.3 0.3 White pepper 0.2 0.2 ───────── ──────────────────────

The physical properties of the sausage gel obtained by the above-mentioned method were measured by Leoner (manufactured by Yamada Denki Co., Ltd.). Jig diameter is 10m
A piercing test was performed at a speed of 300 mm / min using a cylindrical rod of m. The sensory evaluation criteria were the same as in Example 1. The results are shown in Table 3 below.

[0030]

[Table 3] Table 3 ───────────────────────────── Example 3 Comparative Example 1 ────────── ──────────────────── A) Breaking load g 1209 ± 70 989 ± 43 B) Breaking deformation mm 7.0 ± 0.3 6.7 ± 0.2 (A) ÷ (B) 172.71 147.61 Texture ++ ± ──────────────────────────────

As is clear from the results shown in Table 3 above, when the SPI adjusted according to the present invention so that the 7S content is 85% is added, the addition of SPI (A The value of ÷ B) was large, and the sausage which was not crisp and had a crisp feeling was obtained.

[0032]

EFFECTS OF THE INVENTION By using SPI containing 60% or more of 7S globulin which has been preheated in an aqueous system in a gel-like food, it has a better sense of crispness than a conventional SPI and is a non-sticky food. Feeling food is now possible.

[Brief description of drawings]

 (

FIG. 1) A gel obtained by heating a solution having a salt concentration of 2.5% and a protein concentration of 16% at 80 ° C. for 30 minutes. Each protein has SPI prepared from 7S and 11S fractions and SP before fractionation.
It is a fracture deformation curve of I (control).

Claims (2)

[Claims] 1. Denatured by preheating in an aqueous system.
A soy protein containing 60% by weight or more of S globulin (β-conglycinin). 2. A gel food containing salt and the soybean protein according to claim 1.