JP4415244B2 - A food material obtained by the limited action of proteases on wheat protein - Google Patents

Description

【００３１】
実施例１２，１３
実施例２および４の食品素材、それぞれ４ｇに水分が４２％になるように水を加え混捏して、それぞれ実施例１２および１３のドウを作成し、その伸長度を評価した。比較例として、実施例２および４で使用した粉末状小麦蛋白質についても同様に水分が４２％のドウを作成し、その伸長度を評価した（比較例２）。その結果を表２に示す。
【００３２】
【表２】

【００３３】
ここでドウの伸長度はテクスチャーアナライザー（ＳＭＳ社製）を用いて測定した。ドウは付属のドウ成型器で成型し、付属のキーファーのリグによって３．３ｍｍ／秒の速度でドウを引っ張り、ドウが破断した距離（ｍｍ）をその伸長度とした。伸長度の値は比較例の値を１０として表示した。
【００３４】
実施例１４〜１６
実施例５，６および７の食品素材、それぞれ１０ｇに水分が５０％になるように水を加え混捏して、水和物を作成した。それらの水和物を加熱してそれぞれ実施例１４，１５および１６の熱凝固物を作成し、その硬さを評価した。比較例として、実施例５，６および７で使用した小麦蛋白質のドウを凍結乾燥し、同様にその乾燥物の水和物についても熱凝固物を作成し、その硬さを評価した（比較例３）。その結果を表３に示す。
【００３５】
【表３】

【００３６】
ここでの熱凝固物の硬さはレオメーター（レオテック社製）を用いて測定した。作成したドウを内径１０ｍｍ、高さ５０ｍｍのポリプロピレン製の円筒に入れ密栓し、９０℃の湯に３０分間浸漬後、水道水で２時間冷却し熱凝固物を作成した。内径１０ｍｍ、高さ１０ｍｍに調製した熱凝固物を、１．０ｍｍ／秒の速度で圧縮し、２ｍｍ圧縮した時点での荷重を硬さとした。硬さの値は比較例の硬さを１０として表示した。
【００３７】
【発明の効果】
小麦蛋白質にプロテアーゼを限定的に作用させることによって、従来の小麦蛋白質よりもそのドウの伸長性が大きく、また、強い熱凝固性を有する食品素材を得ることができる。とくに、プロテアーゼに酸性プロテアーゼを使用し、ｐＨを１．０〜３．５の条件下で限定的に作用させると、他のプロテアーゼおよび他のｐＨで作用させるときよりも、ドウの伸長性がさらに大きく、また、さらに強い熱凝固性を有する物性にすることができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dough physical property having a large extensibility and a food material having a strong heat coagulation property, which is obtained by subjecting a wheat protein to a limited protease.
[0002]
[Prior art]
Wheat protein forms dough with viscoelasticity that is not found in other proteins when water is retained, and also has functionality such as gas retention and heat coagulation, so it is used as a material for many food processing. Yes. Examples of foods utilizing the dough properties include noodles, confectionery such as bread and biscuits, and batters for frying. Examples of foods using heat coagulation include noodles, fishery products, and livestock products.
[0003]
The demands for improving the workability and the texture of foods in processing these foods are diversified, and conventional wheat protein materials alone cannot satisfy those demands satisfactorily. For example, since noodle making is performed in a low moisture system, dough formation is difficult to proceed, and wheat protein is often added and used for the purpose of improving workability and noodle quality. However, conventional wheat proteins form viscoelastic dough but have low extensibility and are not fully satisfactory in noodle making. Therefore, protein materials having high extensibility and dough physical properties are required. In fishery products and livestock products, wheat protein is used for the purpose of water retention and elasticity, but especially in fishery products such as salmon, bamboo rings and fish sausages, it does not give the color and flavor peculiar to wheat protein. In addition, a protein material that can be elastically reinforced by addition of a small amount, that is, a strong heat-coagulation property is desired.
[0004]
As a method for economically and safely improving the functionality of wheat protein, there is a method of hydrolyzing by the action of protease. However, most conventional methods are hydrolyzed to peptides for the purpose of imparting emulsifying properties, solubility, foaming properties, or use as nutrients, and are different from the purpose of the present invention ( For example, see Patent Document 1, Patent Document 2, and Patent Document 3.) In addition, as a method for improving the heat coagulation characteristic peculiar to wheat protein, a method of partially hydrolyzing wheat protein with protease has been reported, but this method is performed for the purpose of weakening the heat coagulation property. This is also different from the object of the present invention (see, for example, Patent Document 4).
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 08-217795 [Patent Document 2]
Japanese Patent Publication No. 07-57161 [Patent Document 3]
Japanese Patent Laid-Open No. 11-49697 [Patent Document 4]
Japanese Patent Publication No.59-1460 [0006]
[Problems to be solved by the invention]
It is an object of the present invention to provide a food material having a dough physical property that is more extensible than a conventional wheat protein and a strong heat coagulation property.
[0007]
[Means for Solving the Problems]
As a result of diligent research to solve the above-described problems, the present inventors have made proteases act on wheat proteins in a limited manner and hydrolyze some peptide bonds, thereby making them more than conventional wheat proteins. The present inventors have found that the dough physical properties having large extensibility and the physical properties having strong heat coagulation properties are obtained, and the present invention has been achieved based on them.
[0008]
That is, the present invention has a dough physical property having a higher elongation than conventional wheat proteins and a strong heat coagulation property by allowing protease to act on wheat protein in a limited range of 15% or less. It is a food material with improved physical properties.
[0009]
Furthermore, the present invention allows other proteases and other pHs to act on wheat proteins by restricting the action of acidic protease within a range of 8% or less under the condition of pH 1.0 to 3.5. It is a food material that has improved dough physical properties more than ever, and improved physical properties that have stronger heat coagulation properties.
[0010]
Furthermore, the present invention has a higher elongation than conventional wheat proteins by allowing an acidic protease to act on wheat proteins in a limited range of 15% or less under conditions of pH 3.5 to 7.0. A food material with improved dough physical properties and strong thermal coagulation properties. The reaction proceeds slowly because the action of acidic protease deviates from the optimum pH, and the difference in protease addition amount and reaction time This is a method for producing a food material characterized by having a small hydrolysis rate error due to the ability to perform limited hydrolysis of wheat protein with good reproducibility.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The type of wheat protein used in the present invention is not limited. Wheat protein is mainly composed of gluten mainly composed of gliadin and glutenin, and is known to contain proteins such as albumin and globulin.
[0012]
These wheat proteins may be used in the form of flour, a form extracted from wheat flour, or a form obtained by drying the extracted wheat protein. Wheat protein when acting with an acidic protease may be in the form of an aggregated dough containing water, but is dispersed in an aqueous solution containing a solvent such as acetic acid, lactic acid, citric acid, phosphoric acid, hydrochloric acid, sulfuric acid, etc. Is preferred.
[0013]
By allowing protease to act on wheat protein in a limited range with a degree of hydrolysis of 10% or less, the dough can be made softer and more extendable than conventional wheat proteins. In addition, when the degree of hydrolysis of wheat protein is limited within a range of 15% or less, physical properties having stronger heat coagulation properties can be obtained as compared with conventional wheat proteins. The protease is not particularly limited, and the above-described physical properties can be improved by using any of acidic, neutral, and alkaline proteases and animal, plant, bacterial, and fungal proteases.
[0014]
The reason why such physical properties can be obtained is that dough physical properties having a large elongation are due to slippage between protein molecules due to limited hydrolysis of wheat protein. In addition, with regard to physical properties that have strong thermocoagulation properties, the bond between protein molecules is weakened due to limited degradation of peptide bonds, so that the molecular movement of proteins becomes more active. It is speculated that it is formed more than wheat protein. However, if the degradation of the peptide bond exceeds a certain range, the protein structure cannot be maintained. That is, the above-mentioned physical properties can be obtained for the first time within the scope of the present invention by limited hydrolysis of wheat protein.
[0015]
Furthermore, when an acidic protease is allowed to act on wheat protein under a condition where the pH is 1.0 to 3.5 within a range where the hydrolysis degree is 5% or less, it is allowed to act on other proteases and other pH. It is possible to make the dough physical properties that are even more extensible than sometimes. Similarly, when the hydrolysis is limited within a range of 8% or less, it is possible to obtain physical properties having stronger thermocoagulability than when acting at other proteases and other pH. Examples of the acidic protease include a carboxyl group at the active center, such as pepsin, aspartic proteases derived from Aspergillus, aspartic proteases derived from Penicillium, and aspartic proteases derived from Hilotake.
[0016]
The present inventors have found that when an acidic protease is allowed to act on wheat protein under different pH conditions, it shows a different hydrolysis mode (Nippon Food Science and Engineering, held on August 31, 2002). Presented at the 49th Annual Meeting of the Society). The ratio of the low molecular weight decomposition product to the high molecular weight decomposition product increases as the pH to be applied increases to neutrality. Wheat protein has both positively charged amino groups and negatively charged carboxyl groups, so its structure changes with pH. At low pH, the structure of wheat protein molecules is loosened by electrostatic repulsion. It is thought that there is. In other words, when a protease having an optimal pH is allowed to act on the wheat protein molecule in that state, the substrate specificity of the protease also overlaps and the central portion of the wheat protein molecule is cleaved, thereby causing it to act neutrally. I think that the ratio of the low molecular weight decomposition products to the high molecular weight decomposition products may be reduced. By carrying out this degradation mode in a limited manner within a range where the degree of hydrolysis of wheat protein is 8% or less, as described above, the dough is more extendable and heat coagulable than when acting at other proteases and at other pH. It is assumed that enhanced physical properties can be obtained.
[0017]
On the other hand, when an acidic protease is allowed to act on wheat protein in a range of pH 3.5 to 7.0, preferably pH 4.0 to 5.5 within a range where the degree of hydrolysis is 15% or less, as described above. In addition, a food material with improved dough extensibility and heat coagulation properties is obtained, and at the same time, the reaction proceeds slowly because the working pH deviates from the optimum pH, and hydrolysis occurs due to differences in the amount of protease added and reaction time. The speed error is small, and limited hydrolysis of wheat protein can be performed with good reproducibility.
[0018]
The method for recovering the food material obtained by causing protease to act on the wheat protein described above in a limited manner is not particularly limited, and any method can be used. For example, when an acidic protease is allowed to act in the state of a wheat protein dispersion, the dispersion can be pulverized by spray drying, freeze drying, vacuum drying, airflow drying, drum drying, or the like. Alternatively, the food material can be obtained as a dough-like insoluble matter by neutralizing the dispersion to pH 5.0 to 8.0, preferably pH 5.5 to 7.5. When an acidic protease is used, it also plays a role of deactivating or reducing the enzyme activity by deviating from its optimum pH. The insoluble matter can be separated by ordinary solid-liquid separation methods such as centrifugation, filtration and decantation, and dried to be powdered. Moreover, it is as above-mentioned also when protease is made to act in the state where wheat protein is dough.
[0019]
The degree of hydrolysis of wheat protein in the present specification is indicated by the dissolution rate in 4% trichloroacetic acid (TCA), and is expressed by the following formula 1.
[0020]
[Expression 1]
Hydrolysis degree (%) = {(4% TCA dissolved protein mass) / (total protein mass)} × 100
[0021]
The degree of hydrolysis in the content announced at the 49th annual meeting of the Japan Society for Food Science and Technology held on August 31, 2002 is the value obtained by subtracting the amount of 4% TCA-dissolved protein in the protease-inactive wheat protein. This is different from the method for calculating the degree of hydrolysis in this specification.
[0022]
【Example】
Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.
[0023]
Examples 1 and 2
To 16.8 g of commercially available powdered wheat protein (manufactured by Sigma), 183.2 ml of 0.01N acetic acid was added, stirred and dispersed with a homomixer, and adjusted to pH 4.7 with 1N hydrochloric acid. 0.2 g of pepsin (Nacalai Tesque) was added and reacted at 37 ° C. for 40 minutes. The degree of hydrolysis of the wheat protein at this time was 6.2%. Next, the pH was adjusted to 7.0 with 1N sodium hydroxide, and centrifugation was performed to fractionate the dough-like insoluble fraction, which was freeze-dried to obtain a powdery food material (Example 1). . Pepsin was reacted for 90 minutes in the same manner as in Example 1 to obtain a powdery food material (Example 2). At this time, the degree of hydrolysis of the wheat protein was 7.4%.
[0024]
Examples 3 and 4
To 16.8 g of commercially available wheat flour protein (manufactured by Sigma), 183.2 ml of 0.01N acetic acid was added, stirred and dispersed with a homomixer, and adjusted to pH 2.0 with 1N hydrochloric acid. 0.01 g of Nacalai Tesque) was added and reacted at 37 ° C. for 3 minutes. The degree of hydrolysis of the wheat protein at this time was 3.5%. Next, the pH was adjusted to 7.0 with 1N sodium hydroxide, and centrifugation was performed to fractionate the dough-like insoluble fraction, which was freeze-dried to obtain a powdery food material (Example 3). . Pepsin was reacted for 5 minutes in the same manner as in Example 3 to obtain a powdery food material (Example 4). The degree of hydrolysis of the wheat protein at this time was 3.7%.
[0025]
Example 5
Water was added to and mixed with commercially available strong second-class wheat flour (Nisshin Flour Milling) to make dough, and starch was washed away with water to extract wheat protein dough. Add 200 ml of 0.025N acetic acid to 200 g of this wheat protein dough, stir and disperse with a homomixer, add 1.0 g of pepsin (Nacalai Tesque) to the wheat protein dispersion of pH 5.0 and add it at 37 ° C. It reacted for 3 hours. The degree of hydrolysis of the wheat protein at this time was 10.5%. Next, the pH was adjusted to 6.3 with 1N sodium hydroxide, and centrifugation was performed to fractionate the dough-like insoluble section, which was then vacuum-dried to obtain a powdery food material (Example 5). .
[0026]
Example 6
To 200 g of wheat protein dough similar to that in Example 5, 400 ml of 0.025N acetic acid was added, stirred and dispersed with a homomixer, and adjusted to pH 2.0 with 1N hydrochloric acid. Pepsin (manufactured by Nacalai Tesque) 0.05 g) was added and reacted at 37 ° C. for 15 minutes. The degree of hydrolysis of the wheat protein at this time was 4.5%. Next, the pH was adjusted to 6.3 with 1N sodium hydroxide, and centrifugal separation was performed to fractionate the dough-like insoluble section, which was then vacuum dried to obtain a powdered food material (Example 6). .
[0027]
Example 7
0.025N acetic acid (400 ml) was added to 200 g of wheat protein dough similar to that in Example 5, stirred and dispersed with a homomixer, and bacterial-derived neutral protease N Amano G (Amano) was added to the wheat protein dispersion at pH 5.0. 0.01 g of Enzyme) was added and reacted at 40 ° C. for 60 minutes. The degree of decomposition of the wheat protein at this time was 7.5%. Next, the pH was adjusted to 6.3 with 1N sodium hydroxide, centrifugation was performed to fractionate the dough-like insoluble fraction, and it was immediately frozen in liquid nitrogen. It was freeze-dried to obtain a powdered food material (Example 7).
[0028]
Example 8
To 100 g of commercially available powdered wheat protein (manufactured by Sigma), 1000 ml of 0.01N acetic acid was added and stirred and dispersed with a homomixer. 0.5 g) was added and reacted at 40 ° C. for 50 minutes. The degree of hydrolysis of the wheat protein at this time was 5.0%. Next, the pH was adjusted to 6.5 with 1N sodium hydroxide, and centrifugation was performed to fractionate the dough-like insoluble fraction, which was immediately frozen in liquid nitrogen. It was freeze-dried to obtain a powdery food material (Example 8).
[0029]
Examples 9-11
The food materials of Examples 1, 3 and 8 were mixed with 3 g of water so that the water content was 58%, and kneaded to prepare doughs of Examples 9, 10 and 11, respectively, and the elongation was measured. As a comparative example, a dough with a moisture content of 58% was similarly prepared for the powdered wheat protein used in Examples 1, 3 and 8, and the elongation was measured (Comparative Example 1). The results are shown in Table 1.
[0030]
[Table 1]

[0031]
Examples 12 and 13
Water was added to the food materials of Examples 2 and 4 and 4 g of each so that the water content was 42% and kneaded to prepare doughs of Examples 12 and 13, respectively, and the degree of elongation was evaluated. As a comparative example, a dough having a moisture content of 42% was similarly prepared for the powdered wheat protein used in Examples 2 and 4, and the elongation was evaluated (Comparative Example 2). The results are shown in Table 2.
[0032]
[Table 2]

[0033]
Here, the degree of elongation of the dough was measured using a texture analyzer (manufactured by SMS). The dough was molded with an attached dough molding machine, the dough was pulled at a speed of 3.3 mm / second by the attached kerf rig, and the distance (mm) at which the dough broke was defined as the elongation. The value of the elongation was displayed with the value of the comparative example as 10.
[0034]
Examples 14-16
Hydrate was prepared by adding water to 10 g of each of the food materials of Examples 5, 6 and 7 and adding water so that the water content was 50%. These hydrates were heated to prepare thermocoagulated products of Examples 14, 15 and 16, respectively, and their hardness was evaluated. As a comparative example, the wheat protein dough used in Examples 5, 6 and 7 was freeze-dried. Similarly, a heat-coagulated product was prepared for the hydrate of the dried product, and its hardness was evaluated (Comparative Example). 3). The results are shown in Table 3.
[0035]
[Table 3]

[0036]
The hardness of the heat solidified material here was measured using a rheometer (manufactured by Rheotech Co., Ltd.). The prepared dough was put in a polypropylene cylinder having an inner diameter of 10 mm and a height of 50 mm, sealed, immersed in hot water at 90 ° C. for 30 minutes, and then cooled with tap water for 2 hours to prepare a thermally coagulated product. The thermocoagulated material prepared to have an inner diameter of 10 mm and a height of 10 mm was compressed at a speed of 1.0 mm / second, and the load when compressed by 2 mm was determined to be hard. The hardness value was displayed assuming that the hardness of the comparative example was 10.
[0037]
【The invention's effect】
By allowing protease to act on wheat protein in a limited manner, it is possible to obtain a food material having a greater dough elongation and stronger heat coagulation than conventional wheat proteins. In particular, when an acidic protease is used as the protease and the pH is allowed to act under conditions of 1.0 to 3.5, the dough is more extendable than when acting at other proteases and at other pH. The physical properties can be large and have stronger thermal coagulation properties.

Claims (1)

  A food material obtained by causing acidic protease to act on wheat protein at a pH of 1.0 to 3.5 and a hydrolysis degree of 8% or less.