JPS62275669A - Production of yeast extract - Google Patents

Abstract

PURPOSE:To produce a yeast extract having improved flavor and seasoning powder free from a yeast smell, by treating yeast with soft Basidiomycetes. CONSTITUTION:In producing a yeast extract by a conventional procedure, in a proper period of the production process, yeast is treated with a fruit body of soft Basidiomycetes such as Ganoderma lucidum, Pleurotus ostreatus, Lentinus edodes, etc., a mycelium, a ground mold, an extract, a mold culture solution, a supernatant liquid or a mixture thereof, for example, the Basidiomycetes is added to a yeast suspension and brought into contact with the Basidiomycetes for a given time under a condition such as pH, temperature, etc., to readily show enzymatic reactions.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for producing a yeast extract, and more particularly to a method for efficiently producing a yeast extract with improved flavor.

[Conventional technology and its problems]

Yeast extract is used as a natural seasoning for meat extract, vegetable extract,
It has been widely used in recent years because, along with seafood extracts, it has a complex taste that is not found in chemical seasonings.

However, since yeast extract has a unique flavor,
There were problems such as restrictions on the amount of use and applications.

Generally, yeast extract is produced by autolysis or acid decomposition.

It is produced using oxygen decomposition methods, etc., but since the autolysis method uses the enzymatic power of yeast, its action is slow and strong yeast cell walls remain. In addition, in the acid decomposition method, the flavor is not desirable because the acid is used to forcibly heat and hydrolyze the product. Furthermore, although various enzymes are used in the enzymatic decomposition method, many of these enzymes are obtained from molds, groupers, etc., and are not very desirable as food additives.

[Means for solving problems]

As a result of repeated research aimed at improving the flavor, manufacturing conditions, and yield of these yeast extracts, the present inventors found that
This led to the completion of the present invention.

That is, the present invention is a method for producing a yeast extract, which is characterized in that, in producing the yeast extract, a yeast fungus is applied to soften the yeast.

The present invention is classified as a method for producing yeast extract by enzymatic decomposition method, and the method uses soft basidiomycetes such as Mannentake mushroom, Hiratake mushroom, Shiitake mushroom, Nametake mushroom, etc., preferably one or two types of edible and medicinal basidiomycete fungi. Yeast extract is produced using the enzyme obtained by the above culture.

The present invention mainly consists of a step of culturing these fungi and a step of obtaining yeast extract using the culture.

Soft basidiomycetes are usually cultivated on solid wood, sawdust, compost, etc., and their fruiting bodies are often eaten, but these fungi produce cellulose and hemicellulose.

It has enzymatic power to decompose lignin, etc., and also contains various nucleolytic enzymes. The present invention uses the enzymatic power of these basidiomycetes directly or partially to produce a yeast extract, and the basidiomycetes can be used regardless of whether they are fruiting bodies or hyphae. It may also be a crushed product or extract of basidiomycete cells. Furthermore,
The culture solution itself obtained by liquid culturing Basidiomycetes or the supernatant obtained by solid-liquid separation from the culture solution may be used. Moreover, these may be purified. When basidiomycetes are cultured in liquid, strong enzymes accumulate not only in the hyphae but also in the culture solution as the hyphae grow. Therefore, it is possible to use crushed basidiomycete cells or extracts, but culture fluid (
It is easier to use basidiomycetes (with or without basidiomycetes) and is more practical. It goes without saying that these fungi can be used as a mixture.

The medium used for liquid culture of basidiomycetes may be a normal nutrient medium, and there is no need to add special ingredients. Specifically, commonly used culture medium materials such as peptone, meat extract, malt extract, yeast extract, glucose, inorganic salts, etc. may be appropriately combined and used after being diluted with water, and the concentration of each component may be 1 to 5. % is sufficient.

Basidiomycete cultures have strong β-glucanase activity, which is confirmed by the production of reduced plaque from β-glucans (see Figure 1). Using a microscope, it was observed that this enzyme also acts on yeast cell walls and dissolves them. Furthermore, this culture was found to have xylanase activity.

To make yeast act on the basidiomycetes, it can be done at an appropriate time during the yeast extract production process, but usually the basidiomycetes are added to the yeast suspension and the pH, temperature, etc. are adjusted to certain conditions that facilitate the expression of enzyme action. The contact may be made for a period of time (usually 1 to 20 hours). In this case, the concentration of the yeast suspension should be 5 to 45%, preferably 15 to 35%, of the compressed yeast concentration, and when using a liquid culture as the basidiomycete, the yeast suspension should be used after about 1 month has passed after the start of culture. It is preferable to add about 0.3 to 10%, preferably about 1 to 5%. Furthermore, regarding the action temperature and pH of the enzyme, the pH is 4.5 to 9.0, preferably 6.5, as conditions for expressing β-glucanase activity and obtaining a yeast extract with good taste. ~8.5, temperature is 30-60℃, preferably 4
It is preferable to act at a temperature of 0 to 55°C. Further, the yeast may be used in combination with the method for producing yeast extract by autolysis using fresh yeast, or dried yeast or heat-denatured yeast may be used, and there are no particular restrictions.

[Effects and operations of the invention]

According to the present invention, a yeast extract with no yeast odor, improved flavor, and strong taste can be obtained. For example, analysis of the yeast extract obtained in Example 2 revealed that it contained a large amount of amino acids such as glutamic acid, alanine, and lysine, as well as various 5'-nucleotides, especially 5'-nucleotides.
It was found that it contains a large amount of guanylic acid. Therefore, it is recognized that the reason why the yeast extract according to the present invention has excellent taste is due to the interaction between these amino acids and 5'-nucleotides. This suggests that the enzymes contained in the basidiomycetes used in the present invention not only act as cell wall lytic enzymes but also as complex enzymes that include proteolytic enzymes, nucleolytic enzymes, etc. It is thought that it acts in conjunction with the autolytic enzyme system during extract production to amplify its taste.

Moreover, according to the method of the present invention, not only can the manufacturing time of yeast extract be shortened, but also its yield can be improved.

〔Example〕

Next, the present invention will be explained by examples, but the present invention is not limited thereto.

Example 1 2.5 g of powdered yeast extract in wort (temperature approximately 1.5%) 1)
(0.25%) and 20 g (2.0%) of glucose were added and sterilized in an autoclave at 120° C. for 15 minutes. After cooling, this medium was inoculated with Mannentake mushrooms, and 2
Static culture was performed at 0°C.

After about one week, white hyphae are observed on the surface of the culture solution, and if the culture is continued further, after about one month a thick hyphae is formed and the β-glucanase activity reaches its maximum. The filtrate obtained by filtering this culture solution was used as a crude enzyme.

200 g of compressed yeast (21% yeast dry matter) obtained by washing beer yeast was dispersed in water, and 20 ml of the above-mentioned Mannake mushroom crude enzyme was added thereto and water was added to obtain 1). Next, pH 6,
5. The temperature was maintained at 45°C, and after 20 hours, centrifugation was performed to separate the liquid part and the lees part. After adding a certain amount of common salt to the liquid part, it was concentrated and sterilized at a temperature of about 55%. The yeast extract yield at this time was 52%. On the other hand, as a control, the yield of yeast extract obtained in the same manner except that the autolysis method was used without adding crude enzyme was about 10% lower. Furthermore, when the flavor of the yeast extract was investigated through a sensory test (comparison by tasting 2% solutions by four panelists), it was found that the product according to the present invention also had an excellent flavor, as shown in Table 1.

Table 1 ♂L-Evaluation control product Inventive product with yeast odor and slightly poor taste power Example 2: Wort (temperature approx. 1.5%) 1) with meat extract 2 .0g(0,
2%) and glucose 20g (2,0%),
Sterilization was performed in an autoclave at 120°C for 15 minutes.

After cooling, this medium was inoculated with oyster mushrooms and statically cultured at 20°C.

After about one month, the mycelium grown on the surface of the culture solution was collected, ground by adding water, and then centrifuged to obtain a supernatant, which was used as crude enzyme.

45 g of beer dry yeast was dispersed in water, 20 ml of the above-mentioned Hiratake crude enzyme was added, and water was added to prepare 1).

Next, the mixture was maintained at a pH of 8.0 and a temperature of 45° C., and centrifuged after 10 hours to separate a liquid portion and a coarse portion. After adding a certain amount of common salt to the liquid part, it was concentrated and sterilized at a temperature of about 55%.

Analysis of this yeast extract revealed that glutamic acid 4.5%, alanine 3.1%, lysine 2.0%,
It contained 0.6% of 5'-guanylic acid, and had a better flavor than the control yeast extract prepared without the addition of enzyme.

[Brief explanation of drawings]

Figure 1 shows the crude enzyme obtained in Example 1 at pH 6.0 and temperature 45.
It is a graph showing the production rate of reducing sugar over time when it is made to act on β-glucan under conditions of °C.

Claims (3)

[Claims] (1) A method for producing a yeast extract, which comprises reacting yeast with a soft basidiomycete. (2) The method according to claim 1, wherein the soft basidiomycete is selected from Mannentake mushroom, Oyster mushroom, Shiitake mushroom, Nametake mushroom, etc. (3) The method according to claim 1, wherein the soft basidiomycete is a fruiting body, mycelium, a fungal cell fragment or extract, a fungal cell culture solution, a culture supernatant thereof, or a mixture thereof.