JPH08308507A - Production of protein hydrolyzate - Google Patents

Abstract

PURPOSE: To minimize the formation of unhydrolyzed substances and produce a protein hydrolyzate in high yield by treating a raw material protein with a lipolytic enzyme in hydrolyzing a protein with a protease. CONSTITUTION: A protein is reacted with a lipolytic enzyme (preferably a purified enzyme having high phospholipase, lipase or lipoprotein lipase activities) in hydrolyzing a protein with a protease and providing a protein hydrolyzate. The treatment with the lipolytic enzyme may be carried out before the hydrolytic reaction with the protease or simultaneously in the hydrolyzing process with the protease. The treatment with the enzyme is carried out at pH4-9 and 20-60 deg.C temperature by adding the enzyme in an amount of preferably 0.1-5wt.% based on the solid content in a suspension containing the raw material protein in an aqueous solvent. The reactional time is preferably 1-3hr. The hydrolytic reaction with the protease is carried out usually at pH 2-11 and 20-80 deg.C temperature by preferably adding 0.1-5wt.% enzyme based on the solid content thereto. The reactional time is preferably 1-8hr.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a protein hydrolyzate in high yield.

[0002]

2. Description of the Related Art Oligopeptides having an average chain length of 2 to 10 obtained by hydrolyzing a protein with a protease have good digestion and absorption properties, and thus are used as a liquid food, enteral nutrition food, health food and other medical food materials. Alternatively, it is used as a protein material for nutritional drinks such as sports drinks.

In general, when a protein hydrolyzate is produced by degrading a protein with a protease, unfavorable bitterness or unpleasant taste is generated, and the protein or high molecular oligopeptide is insolubilized in the hydrolysis process, and more than a certain degree. In that case, there is a problem that the hydrolysis does not proceed and the desired protein hydrolyzate cannot be obtained in a high yield.

In order to overcome such a problem, the present applicant firstly hydrolyzes a protein in the coexistence of an endo-type protease and an exo-type protease to obtain an oligopeptide having less bitterness in a high yield (Japanese Patent Application Laid-Open No. Sho 60-96). 62-143697).

However, the above method also has a problem that an insoluble fraction rich in undegraded product is generated to some extent and the yield of oligopeptide is not yet sufficient.

Further, a method for producing a protein hydrolyzate having no unpleasant taste in a high yield by using milk protein as a part of a raw material protein when carrying out enzymatic hydrolysis (Japanese Patent Laid-Open No. Hei 6)
-78685) is also proposed, but it is essential to use a considerable amount of milk protein (20 to 70% by weight of the raw material protein is milk protein), and a protein other than milk protein may be used alone or in a mixture. The above problems cannot be overcome in the case of the protein.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides an enzyme hydrolyzate that suppresses the generation of an insoluble fraction rich in undegraded product as much as possible and increases the yield of oligopeptides when a protein is hydrolyzed by a protease to produce a protein hydrolyzate. To provide a decomposition method.

[0008]

Means for Solving the Problems As a result of earnest studies to achieve the above object, the present inventor has found that when a protein is used as a raw material and a protein hydrolyzate is produced using a protease, the enzyme has a lipolytic activity. The inventors have found that the generation of undegraded substances is extremely small by the action of the above, and a protein hydrolyzate can be obtained in a high yield, thus completing the present invention.

The present invention provides a method for producing a protein hydrolyzate, which is characterized in that, when a protein hydrolyzate is produced from a protein as a raw material using a protease, a lipolytic enzyme is allowed to act on the raw material protein. is there.

The present invention will be described in detail below. The raw material protein applied to this invention may be from any source of animal plants, but it is possible to obtain a protein hydrolyzate having no unpleasant taste even from a plant protein raw material that does not use milk protein in combination, As vegetable protein, soybean protein,
Examples thereof include proteins derived from seeds and grains such as wheat protein and corn protein.

As the enzyme used for the lipolytic enzyme treatment of the raw material protein in the present invention, phospholipase, lipase, lipoprotein lipase or the like is used, and these may be of any origin such as plants, animals or microorganisms. . These enzymes may be crude enzymes containing other enzyme activities, such as proteases, phospholipases,
A lipase or a purified enzyme having a high lipoprotein lipase activity is preferable.

[0012] In the treatment with a lipolytic enzyme, usually, 0.01 enzyme is added to the solid content of an aqueous solvent suspension containing a starting protein.
The enzymatic reaction is carried out by adding in the range of 10 to 10% by weight, preferably 0.1 to 5% by weight. The enzyme reaction conditions vary depending on the origin of the lipolytic enzyme used, but generally pH 4-9,
It is carried out at a temperature in the range of 20 to 60 ° C., and if necessary, an activator that promotes an enzymatic reaction, such as calcium ion, can be appropriately added. The reaction time is usually 30 minutes to 5 minutes.
The effect is observed when the reaction is carried out for about 1 to 3 hours. Further, continuous treatment can be carried out by immobilizing the enzyme and performing column reaction. The lipolytic enzyme treatment may be carried out prior to the hydrolysis reaction with the protease or in parallel with the hydrolysis step with the protease.

By treating the raw material protein with a lipolytic enzyme, an enzymatic hydrolysis reaction using a protease is efficiently carried out, and a protein hydrolyzate can be obtained in a high yield which has never been obtained before. . The reason for this is not clear, but in the usual hydrolysis reaction with only protease, the trace amount of lipid in the raw material protein increases relatively in the protein serving as the substrate as the hydrolysis reaction by the protease progresses, and It is presumed that the progress of the reaction may be hindered and the yield may be reduced.

The protein hydrolysis reaction can be carried out by a known method, and usually 0.01 to 10% by weight of enzyme, preferably 0.01 to 10% by weight of the solid content of the aqueous solvent suspension containing the starting protein. The hydrolysis reaction may be carried out by adding in the range of 0.1 to 5% by weight. The protease used in the hydrolysis reaction is not particularly limited, and enzymes of any origin such as animal origin, microorganism origin and plant origin can be preferably used. In addition, it is also optional to use the endo-type protease and the exo-type protease, which are classified according to the degradation mode of these proteases, alone or in combination. Generally pH
It is carried out in the range of 2 to 11,20 to 80 ° C., and usually 30 minutes to
The reaction may be performed for 24 hours, preferably about 1 to 8 hours, and the reaction time may be appropriately determined depending on the degree of decomposition.
Also, continuous reaction can be carried out by immobilizing the enzyme and performing column reaction. However, it is preferable that undesired decay or the like does not occur during the reaction.

When the enzymatic hydrolysis reaction is generally carried out in a batch reaction, the enzyme is inactivated by a method such as heat treatment after the protein hydrolysis reaction. If necessary, the protein hydrolysis reaction product is concentrated by removing the insoluble fraction rich in undegraded product by a method such as centrifugation or membrane separation, and if necessary, freeze-drying or spray-drying. To dry the product.

The protein hydrolyzate obtained as described above is used as a medical food material such as liquid food, enteral nutrition food and health food, or as a protein material such as nutritional supplement drink such as sports drink, Further, it can be preferably used as a raw material for seasonings.

[0017]

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.

Example 1 Isolated soy protein (manufactured by Fuji Oil Co., Ltd .; trade name "Fuji Pro-
R ″) To 100 ml of 5% (W / V) aqueous solution, 67 mg of calcium chloride was added to adjust the pH to 8.0, and phospholipase (manufactured by Novo; trade name “lecitase 10L”) 0.3
3 ml (enzyme solids 0.5 against solids of raw material protein)
%) Was added. Then, the enzyme reaction was carried out at 50 ° C. for 1 hour. No degradation of the raw material protein was observed during this treatment. The enzyme reaction product was adjusted to pH 10 with sodium hydroxide.
Further, 0.2 g (4% based on the solid content of the raw material protein) of protease (manufactured by Daiwa Kasei; trade name "Protin AC10F") was added, and the enzymatic decomposition reaction was carried out at 50 ° C for 5 hours. After the reaction, heat at 100 ° C for 5 minutes to inactivate the enzyme,
After cooling to room temperature, the mixture was centrifuged at 8000 G for 10 minutes to remove the insoluble fraction rich in undegraded matter and neutralized to obtain a protein hydrolyzate. This product has almost no unpleasant taste, and the protein content of the recovered protein hydrolyzate was determined by the Kjeldahl method.
It was as high as 8%.

Comparative Example 1 A protein hydrolyzate was obtained by carrying out only the protease decomposition reaction in the same manner as in Example 1 except that the phospholipase treatment was not carried out. The yield of protein hydrolyzate was 87%.

Example 2 100 ml of a 5% (W / V) aqueous solution of isolated soybean protein was added to p.
After adjusting to H7.0, 25 mg of lipase (manufactured by Amano Pharmaceutical Co., Ltd .; trade name "lipase N") (0.5% of enzyme solids relative to the raw material protein solids) was added, and the enzyme reaction was performed at 50 ° C for 1 hour went. This enzyme reaction product was adjusted to pH 1 with sodium hydroxide.
A protein hydrolyzate was obtained in the same manner as in Example 1 except that the protease treatment was performed, and the yield was 95%.

Example 3 A protein hydrolyzate was obtained by the method of Example 1 except that wheat gluten (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of the isolated soybean protein used in Example 1. The yield of protein hydrolyzate is 9
5%.

Comparative Example 2 A protein hydrolyzate was obtained by carrying out only the protease decomposition reaction in the same manner as in Example 2 except that the phospholipase treatment was not carried out. The yield of protein hydrolyzate was 80%.

[0023]

As described above, according to the present invention, when a protein is used as a raw material and a protein hydrolyzate is produced using a protease, a step of previously treating the raw material protein with an enzyme having a lipolytic activity is performed. This makes it possible to obtain a protein hydrolyzate in a high yield with very little generation of undegraded products.

Claims (2)

[Claims] 1. A method for producing a protein hydrolyzate, which comprises reacting a protein with a lipolytic enzyme when producing a protein hydrolyzate using a protein as a raw material. 2. The method according to claim 1, wherein the lipolytic enzyme is one or more enzymes having phospholipase, lipase or lipoprotein lipase activity.