JP2604301B2 - Yeast extract composition and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yeast extract composition having improved taste and a method for producing the same, and more particularly, to a yeast extract containing both 5'-nucleotides having taste and high free amino acids. The present invention relates to a composition and a method for producing the composition.

[0002]

2. Description of the Related Art Yeast extract not only has excellent taste like meat extract, but also has a complex taste that is not present in chemical seasonings such as sodium glutamate, that is, umami. It has been used widely as a food material because it has unpleasant tastes such as, sour, sour, bitter, bitter and sweet. In addition, various types of yeast extract compositions have been developed and marketed by recent improvements in enzyme utilization technology and separation and purification technology.

[0003] Amino acids, peptides, 5'-nucleotides, carbohydrates, organic acids and the like are known as taste components of yeast extract compositions. Among them, amino acids and peptides are particularly important as components that bring out the unpleasant taste peculiar to the yeast extract composition, and 5′-nucleotide is a component that brings out the umami. The yeast extract composition is usually produced by an autolysis method, an enzymatic decomposition method, or the like.

[0004] In the autolysis method, the content of free amino acids can be increased by the action of protease in yeast cells, but the content of 5'-nucleotide can be extremely low only by the action of coexisting ribonuclease, phosphatase and the like. Was. In order to increase the 5'-nucleotide content, a method of controlling the pH during autolysis is known (see Japanese Patent Application Laid-Open No. 55-92772). However, even in these methods, the solid content yield is 50%. The 5'-nucleotide content described above was still low and was not fully satisfactory.

In the enzymatic decomposition method, yeast cells are heated in advance to deactivate all enzymes possessed by yeast, and then 5'-phosphodiesterase, 5'-adenylate deaminase,
A method of increasing the content of 5'-nucleotides by adding a protease or the like is known (Japanese Patent Application Laid-Open No. 62-20159).
No. 5). In this method, the content of tasteful 5'-nucleotides can be increased to about 4% and a high oligopeptide content can be obtained, but on the other hand, protease sufficiently acts because the yeast protein is denatured by heating. However, there is a problem that the content of free amino acids, which is indispensable for extracting the characteristic flavor of yeast extract, is small.

[0006] As described above, according to the conventionally known simple autolysis method and enzymatic decomposition method, the content of free amino acids is high but the content of tasteful 5'-nucleotides is low, or the content of tasteable 5'-nucleotides is low. Although it was large, only those having a low free amino acid content could be obtained, and it was not possible to obtain a yeast extract composition having high free amino acid content and 5'-nucleotide content, and having excellent flavor and especially good umami. Therefore, since the yeast extract composition does not have the expected characteristic of having an unpleasant taste, there is a problem that the type and amount of food to be used are restricted.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. As a result, the yeast was subjected to autolysis while limiting the temperature and pH to a specific range in combination with a cell wall lysing enzyme. After increasing the solid content yield and increasing the content of a large amount of free amino acids without decomposing the high-molecular RNA, the reaction solution is heated under constant conditions to inactivate the enzyme, and further generate 5'-nucleotide. A method for adding 5'-phosphodiesterase and 5'-adenylate deaminase was found, and it was found that the yeast extract composition thus obtained was excellent in both taste and unpleasant taste, thereby completing the present invention. Reached. Temperature and pH during autolysis in the present invention
In other words, in order to increase the free amino acid content and to suppress the degradation of RNA, and to incorporate a heating step after the autolysis reaction, it is necessary to improve the taste 5 ′ in the subsequent enzyme reaction step.
-It is a very important factor in suppressing the degradation of nucleotides.

Hereinafter, the present invention will be described in more detail. The yeast used in the present invention is not particularly limited as long as it is edible, and yeasts generally used in the food industry such as brewer's yeast, baker's yeast, alcoholic yeast, and yeast for sake can be used. Examples of such yeasts include Saccharomyces cerevisiae (IFO 1954, IFO
0309, IAM 4274), Candida Utilis (IFO 0619, ATCC 15239),
Torulopsis nodaensis (IFO 1942), Torulopsis stellata (IFO 1953), Hansenula anomala (IFO 1150) and the like.

The cell wall lysing enzyme used in the present invention may be any one containing glucanase and mannanase and having sufficient activity to lyse the yeast cell wall. Is YL
-5 (manufactured by Amano Pharmaceutical Co., Ltd.), Tunicase (manufactured by Daiwa Kasei Co., Ltd.), chitarase (manufactured by Kumiai Chemical Co., Ltd.) and the like. At this time, the protease may act to decompose the protein in the cell wall to facilitate lysis.

After suspending the yeast at an appropriate concentration of about 10-15%, the cell wall lysing enzyme is added. The amount of cell wall lytic enzyme added depends on the level of enzyme activity,
Usually, it is about 0.3-3%. Regarding the reaction pH and the reaction temperature, conditions are required to suppress the degradation of the high-molecular RNA and increase the production of free amino acids.
The goal is achieved in the range of 8.5, temperature 45-65 ° C. It is difficult to increase the free amino acid content outside the pH range. When the temperature is below this range, the content of free amino acids increases, but RNA degradation is observed. On the other hand, when the temperature exceeds 65 ° C., the degradation of RNA disappears, but the free amino acid content is extremely reduced.

After the autolysis is performed for about 10-20 hours under the above conditions, the autolysis is performed at 80-120 ° C, preferably 90-10 ° C.
Heat at 0 ° C. to inactivate intracellular enzymes. Heating time is 1
About 0 minutes is enough. Subsequently, 5′-phosphodiesterase and 5′-adenylate deaminase were added to give 5 ′
-Generate nucleotides. The amount of the enzyme added, the enzyme reaction temperature, and the pH are not particularly limited, and may be performed under the minimum conditions for each enzyme.

After the reaction solution is heated to 90 ° C. to inactivate the enzyme, it is centrifuged and the supernatant is concentrated to recover the extract. Although the extract can be used as it is, it may be dried by a method such as spray drying if necessary. The yeast extract thus obtained contains both 5′-inosinic acid and 5′-guanylic acid in an amount of 1 to 5% based on the solid content and 12% or more of free amino acids, and thus has an excellent taste and strong taste. It has a bitter taste and can be used more widely as a food material than conventional products.
Further, since the solid content yield is 50% or more, it is very economically advantageous.

[0013]

EXAMPLES Specific examples will be described below. Example 1 Saccharomyces cerevisiae (IFO 1954) was cultured using a 5% molasses medium, and after collecting and washing, 1000 ml of a yeast slurry (cell concentration: 15%) was prepared. After adjusting the pH to 6, the cell wall lysing enzyme (trade name: YL-5)
1.5 g of [Amano Pharmaceutical Co., Ltd.]
The reaction was performed for 8 hours. Then, the mixture was heated at 90 ° C. for 10 minutes to inactivate the intracellular enzymes, cooled to 70 ° C., and 0.3 g of 5′-phosphodiesterase {trade name: nuclease “Amano” (manufactured by Amano Pharmaceutical Co., Ltd.)} was added. After adjusting to pH 5, 1
The reaction was performed for 0 hours. Subsequently, 0.2 g of 5'-adenylate deaminase {trade name: deamizyme (manufactured by Amano Pharmaceutical Co., Ltd.)} was added to adjust the pH to 5, and the mixture was reacted for 10 hours.
After the reaction, the mixture was treated by a conventional method to obtain 113 g of a yeast extract composition.

The contents of 5'-inosinic acid, 5'-guanylic acid, and free amino acids in the yeast extract composition were determined by high performance liquid chromatography, and the contents were 3.3% and 3.3%, respectively. It was 3.5% and 40%, and the solid fraction was 75.3%. In addition, using brewer's yeast, pH 6,4
The contents of 5'-inosinic acid, 5'-guanylic acid, and free amino acids in the yeast extract composition produced by the autolysis method at 0 ° C were 0.1%, 0.1%, and 30%, respectively. .
In addition, 5′-inosinic acid and 5 ′ in a yeast extract composition produced by an enzymatic method using beer yeast previously inactivated by heating.
Each content of guanylic acid and free amino acid is 2.1
%, 2.2% and 8%.

Next, a sensory test was conducted on these three items to evaluate the two points of umami and savory intensity. A 0.5% solution of each yeast extract composition was prepared and kept at 60 ° C.
A sensory test was conducted by 0 panelists, and the performance was compared. Table 1 shows the results. As is clear from Table 1, the product of the present invention was found to be superior in both umami and savory intensity as compared with the conventional product.

[0016]

Embodiment 2 Candida utilis (IFO 0619)
After culturing using a% molasses medium and collecting and washing cells, 1000 ml of yeast slurry (cell concentration: 15%) was prepared. After adjusting the pH to 6.5, 1.8 g of a cell wall lysing enzyme (trade name: Tunicase [manufactured by Daiwa Kasei Co., Ltd.]) was added, and reacted at 55 ° C. for 18 hours. Thereafter, the mixture is heated at 95 ° C. for 10 minutes to inactivate the intracellular enzymes, then cooled to 70 ° C., and then subjected to nuclease. Product name: nuclease “Amano” [Amano Pharmaceutical Co., Ltd.
Was added and reacted for 9 hours. afterwards,
Reduce the temperature to 45 ° C. Protease
[Amano Pharmaceutical Co., Ltd.] 1.8 g, 5'-adenylate deaminase {trade name: Deamizyme [Amano Pharmaceutical Co., Ltd.]
200 mg) and reacted for 10 hours. After cooling, the mixture was treated by a conventional method to obtain 121 g of a yeast extract composition.

The contents of 5'-inosinic acid, 5'-guanylic acid, and free amino acids in this yeast extract composition were determined by high performance liquid chromatography to find that the contents were 3.1% and 3.1%, respectively. It was 3.3% and 43%, and the solid fraction was 80.7%. In addition, using brewer's yeast, pH 6,4
The contents of 5'-inosinic acid, 5'-guanylic acid, and free amino acids in the yeast extract composition produced by the autolysis method at 0 ° C were 0.1%, 0.1%, and 30%, respectively. .
In addition, 5′-inosinic acid and 5 ′ in a yeast extract composition produced by an enzymatic method using beer yeast previously inactivated by heating.
Each content of guanylic acid and free amino acid is 2.1
%, 2.2% and 8%.

Next, a sensory test was carried out on these three items to evaluate the two points of umami and savory intensity. A 0.5% solution of each yeast extract composition was prepared and kept at 60 ° C.
A sensory test was conducted by 0 panelists, and the performance was compared. Table 2 shows the results. As is evident from Table 2, the product of the present invention was found to be superior in both umami and savory intensity as compared with the conventional product.

[0020]

[0021]

According to the present invention, it is possible to obtain a yeast extract composition having a strong umami and a strong savory intensity which have not been found in the prior art. In addition, it is possible to impart a savory taste, especially umami, to foods whose use has been restricted.

Claims (4)

(57) [Claims] 1. A 5'-inosinic acid and 5'-guanylate a <br/> containing 1-5% each per pair solids, and characterized in that it contains free amino acids pairs solids per 12% or more Yeast extract composition. Wherein by combination of cell wall lytic enzyme yeast was heated to after performing the autolysis, after all deactivated intracellular enzymes, and followed by 5'-phosphodiesterase and 5'-adenylate deaminase to act, the preparation of the yeast extract composition characterized by enhancing both the free amino acid content and tasty 5'-nucleotide content. 3. The autolysis condition is a temperature of 45 to 65 ° C. , pH
The yeast extract composition according to claim 2, which is 5.5 to 8.5.
Manufacturing method of goods . Preparation of the yeast extract composition according to claim 2 or 3 temperature during 4. heating is 80 to 120 ° C..