JPH01179664A - Production of yeast extract - Google Patents

Abstract

PURPOSE:To produce yeast extract having the taste and flavor comparable to those of yeast extract produced by autodigestion using raw yeast as sole raw material, by decomposing dried yeast with enzyme-treated raw yeast. CONSTITUTION:Raw yeast such as baker's yeast or torula yeast is suspended in water at a proper concentration (e.g. about 15%). After adjusting the pH of the suspension to the optimum pH region of the yeast, the suspension is added with an enzyme (preferably cell-wall digesting enzyme) and reacted for 2-5hr under autodigestion condition. The reaction product is added with dried yeast such as beer by-product dry yeast, reacted under autodigestion condition for a total reaction period of 15-24hr, and heated to deactivate the enzyme. The supernatant liquid obtained by centrifugal separation is concentrated to recover the objective extract.

Description

DETAILED DESCRIPTION OF THE INVENTION A.3 Objectives of the Invention-1' The present invention provides a yeast extract using dry yeast and fresh yeast as raw materials, which has taste and flavor comparable to an autolysis method using only fresh yeast as raw materials. The present invention relates to a method for manufacturing.

Previously known methods for producing yeast extract include an autolysis method using fresh yeast as a raw material, an enzymatic decomposition method using dried yeast as a raw material, and a chemical decomposition method using acid or alkali. .

The autolysis method using live yeast as a raw material uses bacterial enzymes to decompose proteins in the yeast cells and produce taste substances such as Ami81 peptides and nucleic acids in a well-balanced manner, resulting in improved quality such as taste and flavor. It is widely used as a method for producing excellent seasonings.

On the other hand, when dry yeast is used as a raw material, the enzymatic decomposition method mainly uses proteolytic enzymes obtained from plants or microorganisms, and the chemical decomposition method uses acid or alkali to decompose the dry yeast and produce the taste substances. Generates amino acid peptides and nucleic acids.

The autolysis method uses a complex enzyme system within the yeast cell to degrade yeast cell proteins, whereas the dry yeast enzymatic degradation method uses a single enzyme system or several types of enzyme systems. Since the chemical decomposition method involves simple hydrolysis with acid or alkali, the forms and proportions of the amino acids and peptides produced will vary slightly, and the taste and flavor will also differ.

The yeast used in the autolysis method is live yeast that has just been cultured, and in order to obtain a yeast extract of good quality, it must be stored and stored to prevent bacterial contamination.
Requires sufficient consideration when handling.

On the other hand, dry yeast yeast is usually heated and dried, so it is easy to store and handle for long periods of time.

1. In order to obtain a yeast extract from dry yeast that has taste characteristics, flavor, etc. comparable to yeast extract obtained by autolysis using live yeast as raw material, dry yeast and live yeast are mixed. Even if an attempt is made to decompose the yeast by the intracellular enzymes of the live yeast under autolytic conditions, only the live yeast will be decomposed, and the dried yeast will hardly be decomposed.

The purpose of the present invention is to efficiently obtain a yeast extract with excellent taste and flavor, which is obtained by an autolysis method of fresh yeast, from dried yeast.

The inventors of the present invention completed the present invention by discovering that by treating live yeast with enzymes, particularly cell wall lytic enzymes, the enzymes within the bacterial cells become active on dry yeast and are decomposed.

Structure of the Invention: The method for producing yeast extract of the present invention is characterized in that dry yeast is decomposed by enzyme-treated live yeast.

A typical example of the dry yeast used in the present invention is beer by-product dry yeast.

Examples of live yeast include baker's yeast for bread production, cultured yeast such as torula yeast from valve waste liquid, and live cells of by-product yeast from beer production.

Suitable enzymes for treating live yeast include those known as cell wall lytic enzymes. Further, a cell wall lytic enzyme and a proteolytic enzyme may be used in combination.

Many of the cell wall-dissolving enzymes currently in use have proteolytic activity.

Cell wall lytic enzyme agents available in Ichi IN include Tunicase (Yamatoka ffllnm), Yt, -5 (Ten!'IJ
commercially available proteolytic enzymes used in conjunction with A-2.
(manufactured by Amano Pharmaceutical ■), Protin FN (manufactured by Daiwa Kasei Mari),
There are Buna Team (manufactured by Nagase Sangyo Kagi), etc. When carrying out the present invention, dry yeast may be added to live yeast that has been enzyme-treated in advance and reacted under autolysis conditions, or fresh yeast and dry yeast may be mixed at the same time, 1g of the ingredient is added, and the reaction is carried out under autolysis conditions. You can let me.

The decomposition reaction conditions applied in carrying out the present invention are based on the autolysis method using live yeast as a raw material, and will be specifically explained below.

Suspend fresh yeast in water to an appropriate concentration, for example, about 15%, adjust the pH to the optimum pH for the enzyme used with acid or alkali, add cell wall lytic enzyme, etc., and incubate for 2 to 5 hours under autolysis conditions.
Allow to react for an hour, then add dry yeast and further react under autolysis conditions for a total of 15 to 24 hours.

Autolysis conditions include pH 3-6 and temperature 30-55°C.
It is appropriate to set the yeast concentration to about 10 to 30%. The ratio of fresh yeast to dry yeast is 10% or more, preferably 30% or more.

In addition, when the proportion of live yeast used in this reaction is small, or in order to further increase the decomposition rate, it is possible to improve the reaction by adding a commercially available proteolytic enzyme.

The reaction solution is heated to 80°C to inactivate the enzyme, then centrifuged, and the supernatant is concentrated and recovered as an extract.

Saccharomyces Cerevi
siae was cultured in molasses medium, centrifugation and washing with cold water were repeated several times, and the sheared live yeast was suspended in water to a concentration of 15%, and 0.5% of the enzyme agent Tunicase F30 was added.
After autolysis at 35°C for 4 hours, beer by-product dry yeast suspended in water to a concentration of 15% was added (fresh yeast: dry yeast = 50:50), and the reaction was continued at 45°C for 13 hours. After the completion of the 0 reaction, centrifuge and concentrate the supernatant under reduced pressure.
Yeast extract was obtained.

The fermented yeast extract was of good quality and had a taste and aroma similar to that of the autolyzed raw yeast extract.

The solid content recovery rate per yeast (dry matter) of yeast extract is 72.
The extract recovery efficiency was high, with a nitrogen recovery rate of 66.4%.

The nitrogen recovery rate (marked 0) and the solids recovery rate (marked O) are shown in FIG. 1 and show higher values than the comparative example described below.

In FIG. 1, the horizontal axis represents the ratio of live yeast to the total amount of dry yeast and live yeast (% by weight), and the vertical axis represents the nitrogen recovery rate or solid content recovery''8 (%).

Shigohan 1 Suspend the live yeast used in Example 1 with water to a concentration of 15%,
After adding 0.5% of the enzyme agent Tunicase F30 and autolyzing it at 35°C for 4 minutes, add beer by-product dry yeast suspended in water to a concentration of 15%. Fresh yeast: Dry yeast = 50:
50), further added 1% of enzyme agent A-2, and continued to react at 50°C for 13 hours. After completion of the reaction, centrifugation was performed, and the supernatant was concentrated under reduced pressure. I mother extract was obtained.

The obtained yeast extract was of good quality and had a taste and aroma close to that of an extract obtained by autolyzing raw yeast.

The solid content recovery rate per yeast (dry matter) of the obtained yeast extract was 82.7%, and the nitrogen recovery rate was 84.6%.

The nitrogen recovery rate (2 mark) and the solid content recovery rate (■ mark) are shown in FIG. 1 and show higher values than the comparative example described below.

The fresh yeast used in Example 1 was suspended in 15% water and
Furthermore, beer by-product dry yeast was suspended to a concentration of 15%, and the ratio of fresh yeast to dry yeast was mixed in a range of 0:100 to 100:0.

The reaction was carried out at 45°C for 17 hours. Each reaction solution was centrifuged and concentrated under reduced pressure to obtain a yeast extract. The solid content recovery rate and nitrogen recovery rate per yeast of the obtained yeast extract are as shown in Table 1.

The nitrogen recovery rate (marked in red) and the solids recovery rate (marked) are shown in FIG.

According to Table 1 and Figure 1, the solid content recovery rate and nitrogen recovery rate increase linearly as the addition ratio of live yeast increases, so it is only due to the decomposition of live yeast, and the decomposition of dry yeast is I can see that very little has happened.

■ By treating fresh yeast with enzymes, especially cell wall lytic enzymes, the complex enzyme system within the live yeast cells acts on dry yeast, resulting in a high yield of high-quality yeast extract.

Effects of the Invention The taste and flavor of the yeast extract obtained by the present invention are greatly improved compared to conventional enzymatically decomposed extracts made from dry yeast, and are comparable to the autolyzed extracts of fresh yeast. Ta.

In addition, by appropriately selecting the ratio of fresh yeast and dry yeast,
Expands the scope of manufacturing applications. That is, the amount of fresh yeast used may be small, and the use of dry yeast, which is easy to handle, will increase, which will be advantageous in terms of production costs and management.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the results of Example 1, Example 2, and Comparative Example.

Claims (1)

[Claims] A method for producing yeast extract, which comprises decomposing dry yeast with enzyme-treated live yeast.