JPH07284369A - Peptide composition and its production - Google Patents

Abstract

PURPOSE:To obtain a peptide composition having extremely low free amino acid content and produced by hydrolyzing a vegetable protein with an enzyme and provide a process for the production of the composition. CONSTITUTION:This peptide composition having a free amino acid content of <=1% based on the total amino acid and composed mainly of a peptide having a molecular weight of 200-4,000 is produced by treating one or more vegetable proteins selected from corn protein, wheat protein, potato protein, soybean protein, etc., with a raw starch decomposition enzyme to effect the decomposition and removal of starch and hydrolyzing the treated product with an alkaline protease forming little free amino acid under highly alkaline condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peptide composition which is obtained by hydrolyzing one or a mixture of two or more vegetable proteins with an enzyme and which comprises a peptide form containing almost no free amino acid and a method for producing the same. Regarding

[0002]

2. Description of the Related Art Heretofore, as a hydrolyzate of a vegetable protein, one obtained by decomposing it with an acid or an enzyme has been known, but recently, it has been obtained by various proteases from a vegetable protein or an animal protein. Peptides have been reported. Peptides have been found to have physiological functions different from those of proteins and amino acids, such as morphine-like analgesic action, immunostimulatory action, blood pressure regulating action, calcium absorption promoting action, and lipid metabolism regulating action.

[0003] Peptides, due to their absorption properties, are also effective nutritional supplements for sports and other severe physical exhaustion, nutritional supplements after surgery, and enteral nutritional supplements as nutritional therapy for various diseases. It can be used effectively.

Major peptides known so far include whey peptide, rice protein-derived peptide, egg white-derived peptide, fish meat protein-derived peptide such as sardines, soybean peptide and wheat peptide.

For example, JP-A-63-287462 discloses the use of soybean peptide as a nutritional supplement, and JP-A-5-236906 discloses a glutamine-rich peptide composition from wheat peptide. It is disclosed that the article is useful as a nitrogen source such as enteral nutrition after surgery.

On the other hand, various health drinks containing various amino acids have been proposed. In this case, since the characteristics differ depending on the type of amino acid, a method of directly adding the amino acid has been adopted in order to exert the function of each amino acid.

[0007]

However, since amino acids generally have a strong bitterness, the flavor is impaired when the added concentration is high, and in the enteral nutritional supplement, a side effect of causing diarrhea when the dose is increased. Therefore, the dose was limited.

Further, in the preparation of enteral nutritional supplements mainly containing amino acids, amino acids can be freely blended, but when considering absorption efficiency or when unstable amino acids such as glutamine are used, the peptide It seems that the state is more effective.

That is, since the amino acid composition of a protein varies depending on its origin, it is possible to obtain a peptide composition containing a large amount of the target amino acid by selecting the type of protein and peptide-mixing these. .

Glutamine, which is unstable in an aqueous solution, is synthesized as a peptide form with other amino acids or is used in the form of a derivative, but if a peptide containing a glutamine derived from a protein is used, these are used. Can solve problems.

On the other hand, considering the nutritional effect, a peptide derived from one kind of protein has a low content of some amino acids depending on the amino acid composition derived from the raw material. As a method of compensating for this, it is possible to add an amino acid directly, but it is ideal to supplement it in the form of a peptide. In this case, peptides from other proteins are effective as the supplemented peptides.

Thus, if various amino acids can be mutually supplemented in the form of peptides, it becomes possible to prepare special nutritional foods, enteral nutritional products and the like corresponding to various pathological conditions.

However, conventional peptide compositions are
Since the type of protease and the enzyme reaction system were not appropriate, free amino acids were likely to be produced, and the reaction with saccharides was likely to occur due to heating such as sterilization during preparation of enteral nutritional supplements. Therefore, not only the coloring and flavor are deteriorated, but also an irritating taste is accompanied, which causes a problem that there is resistance in oral administration.

Therefore, it is an object of the present invention to provide a peptide composition having a very low free amino acid content, which can be freely prepared from various plant proteins selected according to the purpose, and a method for producing the same.

[0015]

Means for Solving the Problems The present inventors have conducted various studies to achieve the above object, and as a result,
Impurities are removed from raw materials containing more than one kind of vegetable protein, and they are hydrolyzed with an alkaline protease under high alkali, and if necessary, an ion exchange resin or an adsorption resin,
It was found that a peptide composition consisting of a peptide containing almost no free amino acid can be obtained by purifying with activated carbon or the like, and completed the present invention.

That is, the peptide composition of the present invention has a molecular weight of 200 obtained by hydrolyzing a vegetable protein with an enzyme.
It is characterized in that it contains ~ 4000 peptides as a main component and the content of free amino acids is 1% or less based on all amino acids.

In the method for producing the peptide composition of the present invention, a raw material containing a vegetable protein is treated with a raw starch degrading enzyme to decompose and remove the starch, and the treated product is treated with a free amino acid under high alkali. It is characterized in that it is hydrolyzed by an alkaline protease that hardly produces

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. In the present invention, various kinds of vegetable proteins can be used, but one or a mixture of two or more selected from corn protein, wheat protein, potato protein, soybean protein is particularly preferably used. Corn protein has a high content of branched chain amino acids, glutamine, alanine, and proline among constituent amino acids, wheat protein has a high content of glutamine and proline, and potato protein has a high content of asparagine, branched chain amino acids, and lysine. Soy protein is characterized by a high content of asparagine, glutamine, lysine, and arginine.

As the corn protein, a corn protein suspension obtained by subjecting corn to wet milling in the manufacturing process of corn starch, for example, a corn gluten meal suspension, a corn gluten liquor, or a corn protein fraction containing 70% of corn protein is used. Tween and the like which are eluted with hydrous alcohol or alkali are preferably used. Further, as the wheat protein, wheat gluten separated from wheat flour is preferably used, and as the potato protein, a protein category obtained by separating from potato is preferably used in the production process of potato starch, and as soybean protein, defatted Soybean powder, concentrated soybean protein, separated soybean protein, defatted soybean milk and the like are preferably used. When using these protein suspensions as raw materials,
The solid content concentration is preferably adjusted to about 5 to 15% by weight.

In the production method of the present invention, these raw materials are previously treated with a raw starch degrading enzyme to decompose and remove the starch. According to a preferred embodiment, an alkali such as sodium hydroxide, potassium hydroxide, calcium hydroxide or the like is added to a suspension of one or a mixture of two or more of the above plant proteins to adjust pH.
Adjust to about 5 to 6, add 0.02 to 0.2 wt% of raw starch degrading enzyme, for example, "Daviase" (trade name, manufactured by Daikin Industries, Ltd.) per raw material solid content, and add 3 to 20 at 50 to 60 ° C.
The starch is decomposed and removed by stirring for a reaction for a time, dehydration and filtration.

Next, the treated product is treated with a solid content concentration of 5 to 20 wt.
%, Preferably 10 to 15 wt% and resuspended, and an alkali such as sodium hydroxide, potassium hydroxide or calcium hydroxide is added to this suspension to adjust the pH to preferably 9%.
More preferably, the pH is adjusted to 12 or more, and the alkaline protease is added at 0.02 to 0.2 wt% per solid material at 50 ° C.
Add and stir at 50-60 ° C. for 3-20 hours to react. This treatment hydrolyzes the vegetable protein to an appropriate length.

The alkaline protease in this case is, for example, “Agric. Biol. Chem, 35 (9), 1407” by Hikoshi et al.
~ 1414 "reported by Bacillu
s. No. 221) derived from alkaline protease (manufactured by Meito Sangyo Co., Ltd.), and "esperase 8.OL" and "sabinase" (trade name, manufactured by Novo Co.) derived from an alkaliphilic mutant strain are preferable. These alkaline proteases have an optimum pH for enzyme action of 10 to 12, and have excellent heat resistance,
Usually, it is an endo-type enzyme, and it is an enzyme that hardly produces free amino acids.

The peptide composition of the present invention can be obtained, for example, by the above-mentioned production method. In commercialization, if necessary, the final treatment solution is concentrated and the pH is adjusted, followed by acid treatment or amidase. , Bitterness is reduced by enzyme treatment such as deaminase, desalting treatment is performed by ion exchange resin, ion exchange membrane, reverse osmosis membrane (RO membrane), activated carbon treatment, sterilization treatment, evaporation to dryness and powderization. It is preferable. However, depending on the application, the solution may be used as it is.

In the present invention, in order to obtain a peptide having a desired amino acid composition, two or more peptide compositions obtained by using different types of plant proteins as raw materials are mixed to obtain a final peptide composition. You can also get things.

The peptide composition of the present invention comprises a vegetable protein hydrolyzed with an enzyme as described above, which is mainly composed of a peptide having a molecular weight distribution of 200 to 4,000 and an average molecular weight of about 500 to 2,000, and a free amino acid content. Is 1% or less with respect to all amino acids. The components of this peptide composition are
As a preferred example, the solid content is composed of 80 to 99% by weight of peptide, 2 to 10% by weight of sugar, 0 to 1% by weight of amino acid, and 0 to 5% by weight of others.

The preferred peptide composition of the present invention has an amino acid composition as shown in Table 2 below.

[0027]

[Table 2]

[0028]

The peptide composition of the present invention is mainly composed of a peptide having a molecular weight distribution of 200 to 4,000, which is obtained by hydrolyzing a vegetable protein with an enzyme, and like the amino acid, the absorption from the digestive tract is rapid. Moreover, since it is good, it is suitable as a nutritional supplement when physical strength decreases due to intense exercise, or as an enteral nutritional supplement for the condition of poor digestive function.

Since the peptide composition of the present invention contains almost no free amino acids, it has less bitterness than amino acids, has improved odor and taste, and has unstable glutamine in the form of peptides. In addition, amino acids that tend to be deficient can be supplemented with peptides derived from other proteins, so that they can be applied to a wide range of foods.

According to the production method of the present invention, free amino acids are removed by removing the impurity starch from the vegetable protein, hydrolyzing it with an alkaline protease under high alkali, and further purifying it if necessary. It is possible to industrially and efficiently produce a peptide composition having a peptide form containing almost no peptide.

[0031]

EXAMPLES The present invention will now be described in more detail with reference to examples. Example 1 Sodium hydroxide was added to 450 L of corn protein category obtained from the wet milling step in the production of cornstarch to adjust the pH to 5.5, and a raw starch degrading enzyme "Daviase" (trade name, Daikin Industries Ltd.) Company made) 70
After adding g and reacting at 50 ° C. for 5 hours, solid-liquid separation is performed with a filter press to obtain 90 kg of wet cake of corn protein.

This wet cake was resuspended in 350 L of distilled water, sodium hydroxide was added to adjust the pH to 12, and 80 g of a highly alkaline protease derived from alkalophilic bacteria (manufactured by Meito Sangyo Co., Ltd.) was added, Incubate for 20 hours while adjusting pH to 9.0. The reaction solution is subjected to solid-liquid separation with a filter press to obtain an enzymatic hydrolyzate of corn protein.

The above hydrolyzate is desalted with an ion exchange resin, decolorized with an adsorption resin, deodorized, treated with activated carbon and sterilized by heating, concentrated and dried to obtain a corn peptide composition as a white powder.

Example 2 The same procedure as in Example 1 was repeated except that the corn protein in Example 1 was replaced with wheat protein and dried to obtain a wheat peptide composition which was a white powder.

Example 3 The corn protein in the above Example 1 was replaced with the potato protein, and the same operation as in Example 1 was repeated and dried to obtain a potato peptide composition which was a pale yellow powder.

Example 4 The corn protein in the above Example 1 was replaced with defatted soybean protein, and the same operation as in Example 1 was repeated and dried to obtain a soybean peptide composition which was a pale yellow powder.

Example 5 200 L of corn protein category in Example 1 above
To this, 22 kg of wheat protein is added, the same operation as in Example 1 is repeated, and dried to obtain a corn + wheat peptide composition as a white powder.

Example 6 200 L of corn protein category in Example 1 above
Then, 20 kg of potato protein is added thereto, and the same procedure as in Example 1 is repeated to obtain a corn + potato peptide composition which is a white powder after drying.

Example 7 20 kg of wheat protein and 20 kg of isolated soybean protein were suspended in 400 L of water, and sodium hydroxide was added to adjust the pH to 5.5. The raw starch degrading enzyme "Daviase" (trade name) (Manufactured by Daikin Industries, Ltd.) and reacted at 50 ° C. for 5 hours, and then the same operation as in Example 1 is repeated and dried to obtain a wheat + soybean peptide composition which is a pale yellow powder.

Test Example 1 The amino acid compositions of the peptide compositions obtained in Examples 1 to 7 are shown in Tables 3 and 4. It should be noted that data of tryptophan, which is an aromatic amino acid, is not shown in Tables 3 and 4 because it contains almost no tryptophan.

[0041]

[Table 3]

[0042]

[Table 4]

Test Example 2 The peptide composition obtained in Example 1 was applied to an amino acid automatic analyzer to measure the amount of free amino acid (ng per 1 mg) by ninhydrin color development.

[0044]

[Table 5]

Test Example 3 The peptide compositions obtained in Examples 1 to 7 and the aromatic amino acids tyrosine and phenylalanine as controls were analyzed by high performance liquid chromatography (HPLC), and the molecular weights of the peptide compositions were analyzed. The distribution and the amount of free amino acids were determined respectively.

[OH Pak KB-802.5] as a separation column
(Trade name, manufactured by Showa Denko KK) using 0 to 1% trifluoroacetic acid-40% acetonitrile eluent,
The flow rate was 0.5 ml / min., And the detector was UV270 nm for analysis.

The results of this analysis are shown in Tables 6 and 7. Tables 6 and 7
Shows the elution positions compared in time. Moreover, the elution curve when the peptide composition obtained in Example 1 was subjected to high performance liquid chromatography (HPLC) is shown in FIG.

[0048]

[Table 6]

[0049]

[Table 7]

In Table 5, the free amino acid amounts of tyrosine and phenylalanine of the peptide composition obtained in Example 1 are 40.69% and 33.56%, respectively.
27%. In Table 5, it is considered that the peptide classification was developed by ninhydrin and was detected. Therefore, judging from Tables 6 and 7, the free amino acid content of the peptide compositions of Examples 1 to 7 was 1.0% or less. Recognize.

[0051]

As described above, the peptide composition of the present invention has a molecular weight obtained by enzymatically decomposing a vegetable protein.
Since 200 to 4,000 peptides are the main components, absorption from the digestive tract is rapid and good, similar to amino acids, and it can be used as a nutritional supplement when physical strength decreases due to vigorous exercise or in conditions with insufficient digestive function. Suitable for enteral nutrition.

Further, since the peptide composition of the present invention contains almost no free amino acids, it has less bitterness than amino acids and has improved odor, taste and the like. Further, unstable glutamine can be present in the form of a peptide, and amino acids that tend to be deficient can be supplemented with peptides derived from other proteins, so that it can be applied to a wide range of foods.

Furthermore, according to the production method of the present invention, the starch is removed from the vegetable protein and hydrolyzed with an alkaline protease under high alkali to industrially produce a peptide composition containing almost no free amino acid. It can be manufactured efficiently.

[Brief description of drawings]

FIG. 1 is a chart showing an elution curve when the peptide composition obtained in Example 1 was subjected to high performance liquid chromatography (HPLC).

Claims (10)

[Claims] 1. A main component is a peptide having a molecular weight of 200 to 4000 obtained by hydrolyzing a vegetable protein with an enzyme,
A peptide composition having a free amino acid content of 1% or less based on all amino acids. 2. The peptide composition according to claim 1, which contains peptides obtained from a plurality of types of plant proteins. 3. The peptide composition according to claim 1 or 2, which contains a peptide obtained from one kind or two or more kinds selected from corn protein, wheat protein, potato protein and soybean protein. 4. The peptide composition according to claim 1, which has the amino acid composition shown in Table 1 below. [Table 1] 5. 80 to 99% by weight of the peptide in the solid content,
Sugar 2-10% by weight, amino acids 0-1% by weight, other 0
The peptide composition according to any one of claims 1 to 4, containing 5% by weight. 6. A raw material containing a vegetable protein is treated with a raw starch degrading enzyme to decompose and remove the starch, and the treated product is hydrolyzed with an alkaline protease which hardly produces a free amino acid under high alkali. A method for producing a peptide composition, comprising: 7. The method for producing a peptide composition according to claim 6, wherein one or a mixture of two or more selected from corn protein, wheat protein, potato protein and soybean protein is used as a raw material. 8. The method for producing a peptide composition according to claim 6, wherein an endo-type enzyme derived from an alkalophilic bacterium is used as the alkaline protease. 9. The treated product with the raw starch degrading enzyme is adjusted to pH.
The method for producing the peptide composition according to any one of claims 6 to 8, which is adjusted to 9 or more to act on the alkaline protease. 10. The mixture of two or more peptide compositions obtained by using different kinds of vegetable proteins as raw materials.
10. A method for producing the peptide composition according to any one of 9 to 10.