JP2003325130A - Method for producing yeast extract - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a yeast extract having high deliciousness, thickness and saltiness, improved seasoning property and decreased yeast smell. <P>SOLUTION: The yeast extract is produced by treating yeast cells under high pressure, treating with an endo-type protease and then treating with an exo-type protease. <P>COPYRIGHT: (C)2004,JPO

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 yeast extract, and more particularly to a method for producing a yeast extract having a strong umami, rich and salty taste, improved taste and further reduced yeast odor.

[0002]

2. Description of the Related Art Yeast extract has recently been used as a natural seasoning.
Along with meat extract, vegetable extract, seafood extract, etc., complex tastes that chemical seasonings do not have, that is, umami, sourness,
It has bitterness and richness and is widely used as a food material.

Conventionally, as a method for producing a yeast extract, there are a natural decomposition method such as an autolysis method and a hot water extraction method, an enzymatic decomposition method, and a chemical decomposition method such as an acid / alkali or a salt. Various proposals have been made for the purpose of enhancing sexuality and reducing yeast odor.
A method of extracting an extract from the yeast cells by applying an ultrahigh pressure of about / cm 2 or more (JP-A-2-255059),
A method of mechanically crushing the cell wall of yeast and extracting components in the yeast (Japanese Patent Laid-Open No. 252894/1993), autolysis using cell wall lysing enzyme in combination, followed by heating to remove intracellular enzyme After inactivation, 5'-phosphodiesterase, 5 '
-A method of increasing the taste 5'-nucleotide content and the free amino acid content by allowing adenylate deaminase to act (JP-A-6-70716), and a yeast cell suspension treated with a high-pressure homogenizer at pH 6.5 to 8 .5 neutrality ~
A method of adjusting to weakly alkaline, adding an enzyme agent containing an endo-type protease to the yeast cell suspension, and performing self-digestion (JP-A-9-56361), in producing a yeast extract by the self-digestion method, A method of production using two-step enzyme reaction temperature conditions (Japanese Patent Application Laid-Open No. 10-179084).
Gazette), an aqueous suspension of yeast at 90 to 95 ° C. for 30 to 6
After 0 minute heat treatment, a method of simultaneously reacting a lysing enzyme, a nuclease, a deaminase, and an enzyme composed of 1% by weight or more of protease with respect to the dry matter of yeast at 40 to 70 ° C. (JP-A-10-262605) Is proposed.

[0004]

Although the above-mentioned methods proposed hitherto have some effects, they are not sufficiently satisfactory in terms of enhancing the taste of yeast extract and reducing yeast odor.

[0005] Therefore, an object of the present invention is to provide a method for producing a yeast extract having a strong umami, a full-bodied taste, a strong salty taste, an improved taste and a reduced yeast odor.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that this time, yeast cells were treated with high pressure, treated with endo-type protease, and then exogenous. It has been found that a yeast extract having a strong umami and rich taste, improved taste and reduced yeast odor can be obtained by the action of a type protease, and the present invention has been completed.

Thus, according to the present invention, yeast cells are
For example, after high-pressure treatment within the range of 0 to 0.8 MPa,
There is provided a method for producing a yeast extract, which comprises treating with an endo-type protease and then allowing the exo-type protease to act.

The present invention will be described in more detail below.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The yeast used in the present invention is not particularly limited as long as it is edible, for example, baker's yeast,
What is used in normal food industry, such as brewer's yeast, alcohol yeast, and sake yeast, can be used alone or in combination. Examples of such yeasts include yeasts belonging to the genera Saccharomyces and Candida.

The method for producing a yeast extract of the present invention is characterized in that the above-mentioned yeast cells are subjected to a high pressure treatment, then treated with an endo-type protease, and then treated with an exo-type protease.

First, a method for high-pressure treatment of yeast cells will be described. For example, water of 0.
8 to 2.0 parts by weight is added, and the mixture is filled in an appropriate pressure device such as an autoclave and subjected to high pressure treatment. The conditions for the high pressure treatment are, for example, 0 to 0.8 MPa, preferably 0.1
At a pressure in the range of ~ 0.2 MPa, 100-180 ° C,
Preferably, 5 to 30 under a temperature condition of 100 to 120 ° C.
Minutes, preferably 15 to 20 minutes. By performing the high-pressure treatment, the extract components such as intracellular proteins and nucleic acids can be easily extracted, and the efficiency of the protease treatment described below can be increased.

Next, this high-pressure treated product is treated with endo-type protease. The endo-type protease that can be used in the present invention is not particularly limited, and at least one endo-type protease derived from plants and animals and derived from microorganisms is used.
More than one kind can be used, for example, bacteria-derived thermolysin, koji mold-derived deuterolysin, actinomycete-derived neutral protease, plant-derived papain, bromelain, animal-derived trypsin, pepsin, cathepsins and the like. You can Specifically, for example, bacterial-derived thermolysin such as Protease N (manufactured by Amano Enzyme), Neutrase (manufactured by Novo Nordisk Bioindustry), Orientase 10NL (manufactured by HBII); Sumiteam FP (Nippon Kagaku Kogyo) Deuterolysin derived from Aspergillus oryzae such as orientase ONS (manufactured by HBI) or Protease M (manufactured by Amano Enzyme); actinase AS (manufactured by Kaken Pharma) or other neutral protease derived from actinomycetes;
Plant-derived neutral proteases such as papain W-40 (manufactured by Amano Enzyme) and bromelain (manufactured by Nippon Biocon); animal origins such as trypsin PTN (manufactured by Novo Nordisk Bioindustry) and pepsin (manufactured by Nippon Biocon) Proteases; cathepsin such as squid liver-derived cathepsin D.

The amount of the endo-type protease to be used cannot be generally stated depending on the titer and the like, but for example, it can be exemplified in the range of 0.1 to 100 U / g based on the weight of the yeast.

The treatment conditions with endo-type protease are as follows:
It is not particularly limited and can be carried out in accordance with the optimum conditions of the enzyme to be used, but it is usually adjusted to a pH range of 4 to 8 and treated at a temperature range of 25 to 70 ° C. for 1 to 24 hours. The method may be illustrated.

In the present invention, after treated with the above-mentioned endo-type protease, the treated product is further treated with an exo-type protease. The exo-type protease that can be used in the present invention is not particularly limited, and at least one or more animal- or plant-derived exo-type proteases derived from microorganisms can be used. For example, acid carboxypeptidase derived from koji mold, yeast-derived Examples thereof include acid carboxypeptidase, squid liver-derived carboxypeptidase, wheat-derived carboxypeptidase, and koji mold-derived aminopeptidase, bacterial-derived aminopeptidase, maitake-derived aminopeptidase, and the like. Specifically, for example, carboxypeptidase P
(Manufactured by Sigma-Aldrich), Sumiteam FLPA (manufactured by Shin Nippon Chemical Industry Co., Ltd.), protease M (manufactured by Amano Enzyme) and other acidic carboxypeptidases derived from koji mold; carboxypeptidase Y (manufactured by Sigma-Aldrich) and other yeast-derived acidic Carboxypeptidase; animal-derived acidic carboxypeptidase such as squid liver carboxypeptidase; plant-derived acidic peptidase such as carboxypeptidase W (manufactured by Pentel), maitake-derived aminopeptidase; amino acid derived from Aspergillus oryzae such as sacanase (manufactured by Kaken Pharma Co.) Examples thereof include peptidases; aminopeptidases derived from bacteria such as accelerators (manufactured by Manyutsusho Co., Ltd.).

The amount of exo-type protease used cannot be generally determined depending on the titer and the like, but for example, it can be exemplified in the range of 0.1 to 100 U / g based on the weight of yeast cells.

The treatment conditions with exo-type protease are as follows:
It is not particularly limited and can be carried out in accordance with the optimum conditions of the enzyme to be used, but usually, for example, in the case of carboxypeptidase, it is adjusted to a pH range of 2.5 to 5, and in the case of aminopeptidase, , A pH range of 6 to 8.5, and a temperature range of 20 to 60 ° C. for 1 to 24 hours.

As an example of one embodiment of the present invention, 0.8 to 2.0 parts by weight of water is added to 1 part by weight of yeast cells, and a pressure condition of about 0.1 to about 0.2 MPa is applied. About 100 to about 1
After high-pressure treatment at 20 ° C. for about 10 to about 20 minutes, the mixture is cooled, and the above-mentioned endoprotease is added to about 30 to about 60.
Enzyme treatment is performed at 60 ° C. for about 60 minutes to about 24 hours. After the enzyme treatment, the pH is adjusted to 2.5 to 5.0, and then the above-mentioned exo-type protease is added, and the pH is adjusted to about 60 at about 20 to about 60 ° C.
The enzyme treatment is performed for about 24 minutes to about 24 hours. After the enzyme treatment, the pH is adjusted, the enzyme is inactivated at about 90 to about 100 ° C. for about 5 to about 20 minutes, then cooled, and clarified by separating using an appropriate separating means such as centrifugation or filter paper filtration. The yeast extract can be obtained. The obtained yeast extract may be in the form of a concentrated liquid by adopting an appropriate concentration means, if desired.
The yeast extract of the present invention is usually used in a liquid state as it is, but if desired, an excipient such as dextrin, modified starch, cyclodextrin, gum arabic or the like may be added to the extract to give a powder form.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples.

[0020]

Example 1 To 100 g of yeast cells, 200 g of water was added and suspended, and then autoclaved at 120 ° C. and 0.2 MPa.
It was heated and pressure-treated for 15 minutes (hereinafter referred to as pressure-treated product A). This pressure treatment A is cooled to 60 ° C.
10 mg of orientase 90N (endo-type protease manufactured by HBI) was added at u / g and reacted at 60 ° C. for 5 hours (hereinafter referred to as enzyme-treated product B). The pH of this enzyme-treated product B was adjusted to 4.0 with 0.1N hydrochloric acid, and then 0.05 g of 50 u / g of protease M (exo-type protease manufactured by Amano Enzyme) was added at 40 ° C. to 40 The reaction was carried out at 0 ° C for 20 hours (hereinafter referred to as enzyme-treated product C; product 1 of the present invention).

(Comparison of Gel Filtration Curves) Pressurized product A in the above step, enzymatically processed product B after the first step endo-type protease treatment and enzymatically processed product C after the second step exo-type protease treatment (main Invention 1) is superdex
Peptide (manufactured by Amersham Pharmacia) was used for gel filtration chromatography to measure the molecular weight distribution. Fig. The chromatogram is shown in Fig. 1. In the pressure-treated product A and the enzyme-treated product B, a large amount of peptides having a molecular weight of 1000 to 500 Da is produced, and in the enzyme-treated product C (invention product 1), peptides / amino acids having a molecular weight of 500 Da or less are produced. Generated in large quantities. From this, it was confirmed that by pressurizing the yeast cells, both proteases act and a large amount of taste components are produced.

(Comparison of Free Amino Acid Content) The free amino acid content in the reaction solution was measured by the ninhydrin coloring method.
The results of pressure-treated product A, enzyme-treated product B, and enzyme-treated product C (invention product 1) are shown in FIG. As shown in Fig. 2, it was confirmed that a large amount of free amino acids was released from the yeast cells by the two-step enzymatic reaction.

(Comparison of taste and aroma) The water-soluble portion of the pressure-treated product A, the enzyme-treated product B and the enzyme-treated product C (product 1 of the present invention) was separated and diluted with a 5% solution to prepare 10 specialized panelists. The sensory evaluation was performed by. As a result, all 10 professional panelists
The enzyme-treated product C (invention product 1) in both taste and aroma has a very strong umami as compared with the pressure-treated product A and the enzyme-treated product B.
It was evaluated that a rich and salty taste was felt.

Comparative Example 1 (example in which pressure treatment was not carried out in Example 1) 200 g of water was added to 100 g of yeast cells and suspended, and then the suspension was heated to 60 ° C. (hereinafter, enzyme-untreated product). Called D). 5000u / g of Orientase 90N
10 mg (manufactured by HBI) was added and reacted at 60 ° C. for 5 hours. After adjusting the pH of this reaction solution to 4.0 with 0.1N hydrochloric acid, 0.05 g of 50 u / g Protease M (manufactured by Amano Enzyme) was added at 40 ° C.,
Reacted at 40 ° C for 20 hours (hereinafter referred to as enzyme-treated product E
Called)).

(Comparison of gel filtration curves) The enzyme-untreated product D and the enzyme-treated product E were subjected to gel filtration chromatography using Superdex peptide (manufactured by Amersham Pharmacia) to measure the molecular weight distribution. Fig. A chromatogram is shown in Fig. 3, and there was almost no change between the enzyme-untreated product D and the enzyme-treated product E, and it was confirmed that the protease did not act.

(Comparison of Free Amino Acid Content) The free amino acid content in the reaction solution was measured by the ninhydrin coloring method.
The results are shown in Fig. As shown in Fig. 4, almost no change was observed due to the enzymatic reaction.

(Taste and aroma comparison) The water-soluble parts of the enzyme-untreated product D and the enzyme-treated product E were separated, diluted with a 5% solution, and subjected to sensory evaluation by 10 specialized panelists. As a result, all the expert panelists evaluated that there was no difference in taste and aroma between the enzyme-untreated product D and the enzyme-treated product E.

Example 2 To 100 g of yeast cells, 200 g of water was added and suspended, and then heated and pressurized in an autoclave at 130 ° C. and 0.26 MPa for 15 minutes (hereinafter, pressure treatment). Object F
Called)). This pressurized product F is cooled to 60 ° C. and
5 mg of an actinomycete-derived neutral endoprotease of 0000 u / g was added and reacted at 60 ° C. for 5 hours (hereinafter, referred to as enzyme-treated product G). PH of this enzyme-treated product G
Was adjusted to 4.0 with 0.1N hydrochloric acid, and then wheat-derived acid carboxypeptidase (50 u / g) 0.0
5 g was added and reacted at 40 ° C. for 20 hours (hereinafter, referred to as enzyme-treated product H; product 2 of the present invention).

(Comparison of Gel Filtration Curves) Pressurized product F by the above process, enzyme-treated product G after the first step endo-type protease treatment and enzyme-treated product H after the second step exo-type protease treatment ( Invention 2) is superdex
Peptide (manufactured by Amersham Pharmacia) was used for gel filtration chromatography to measure the molecular weight distribution. Fig. The chromatogram is shown in Fig. 5, and the pressure-treated product F
The enzyme-treated product G produced a large amount of peptides having a molecular weight of 1000 to 500 Da, and the enzyme-treated product H (product 2 of the present invention) produced a large amount of peptides / amino acids having a molecular weight of 500 Da or less. From this, by pressurizing the yeast cells,
It was confirmed that both proteases act and a large amount of taste components are produced.

(Comparison of Free Amino Acid Content) The free amino acid content in the reaction solution was measured by the ninhydrin coloring method.
The results of the pressure-treated product F, the enzyme-treated product G, and the enzyme-treated product H (invention product 2) are shown in FIG. As shown in 6, it was confirmed that a large amount of free amino acids was released from the yeast cells by the two-step enzymatic reaction.

(Comparison of taste and aroma) The water-soluble parts of the pressure-treated product F, the enzyme-treated product G and the enzyme-treated product H were separated, diluted with a 5% solution and subjected to a sensory evaluation by 10 professional panelists. It was As a result, all the expert panelists taste and smell the enzyme-treated product H (invention product 2) more strongly than the pressure-treated product F and the enzyme-treated product G, and feel a very strong umami, rich taste, and salty taste. It was evaluated as being able to.

[0032]

EFFECTS OF THE INVENTION According to the present invention, it is possible to provide a method for producing a yeast extract which has a strong umami taste, a rich taste and a salty taste, an improved taste and a reduced yeast odor.

[0033]

[Brief description of drawings]

FIG. 1 is a drawing showing molecular weight distributions of a pressure-treated product A, an enzyme-treated product B, and an enzyme-treated product C by gel filtration chromatography.

FIG. 2 is a drawing showing the amounts of free amino acids of pressure-treated product A, enzyme-treated product B, and enzyme-treated product C.

FIG. 3 is a drawing showing the molecular weight distributions of pressure-treated product D and enzyme-treated product E by gel filtration chromatography.

FIG. 4 is a drawing showing the amounts of free amino acids of pressure-treated product D and enzyme-treated product E.

FIG. 5 is a drawing showing the molecular weight distributions of pressure-treated product F, enzyme-treated product G, and enzyme-treated product H by gel filtration chromatography.

FIG. 6 is a drawing showing the amounts of free amino acids of the pressure-treated product F, the enzyme-treated product G, and the enzyme-treated product H.

Claims (2)

[Claims] 1. A method for producing a yeast extract, which comprises treating a yeast cell with a high pressure, treating with an endo-type protease, and then allowing an exo-type protease to act thereon. 2. The manufacturing method according to claim 1, wherein the high-pressure treatment is performed at a pressure within a range of 0 to 0.8 MPa.