JPH06197749A - Production of liquors - Google Patents

Abstract

PURPOSE:To suppress the production of diacetyls in continuously producing liquors such as beer and efficiently obtain the liquors having stable flavor in a short time by using an immobilized yeast having the surface covered with a gel. CONSTITUTION:Liquors are obtained by a method for usually fermenting a sterilized brewing raw material solution at 10-15 deg.C under anaerobic conditions by using an immobilized yeast having the surface covered with a gel. The immobilized yeast having the surface covered with the gel is preferably obtained by simultaneously dropping a mixed turbid solution of a yeast with an aqueous solution of a substance having gelling ability from an inner pipe of a double-pipe nozzle and an aqueous solution of a substance having the gelling ability from an outer pipe into a gelling agent, gelatinizing the substances and forming another gel layer on the outer layer of the gel immobilizing the yeast. Furthermore, when sodium alginate is used as the substance having the gelling ability, calcium chloride, barium chloride, etc., can be used as the gelling agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing alcoholic beverages,
More specifically, the present invention relates to a method for producing a liquor having a stable flavor in a short period of time by suppressing the production of diacetyls by using an immobilized yeast whose surface is coated with a gel. The alcoholic beverages to which the present invention is applied include beer, sake, and wine, and beer is particularly preferable.

[0002]

2. Description of the Related Art Alcoholic beverages are generally produced by adding yeast to a brewing raw material liquid and the yeast metabolizing a substrate to produce ethyl alcohol. In this case, diacetyls are inevitably produced as a by-product. Here, the diacetyls collectively refer to vicinal diketones such as diacetyl and pentanedione, and acetolactic acids such as acetolactic acid and acetohydroxybutyric acid, which are precursors thereof.

Most of the diacetyls produced in the fermentation early stage in the production of alcoholic beverages and present in the fermentation broth are vicinal diketone precursors, and as such are not decomposed by the microorganisms used, that is, yeast, and become vicinal diketone bodies. It will be disassembled for the first time. However, the reaction in which the vicinal diketone precursor is converted to the vicinal diketone body is a non-biological pure chemical reaction, and therefore the late fermentation period is performed at a relatively low temperature, which slows down this chemical reaction. It becomes the rate-determining factor, and it takes a long time to produce alcoholic beverages having a low diacetyl concentration.

Various methods have been proposed for continuous production of alcoholic beverages. For example, a technique for immobilizing yeast by encapsulating it in a water-containing gel has advanced, and thus the immobilized yeast thus obtained is used. A continuous wort brewing method has been proposed
[J.Inst.Brew., 84, 228 (1978) and EBC Congress, Pro.
c., 505 (1981)]. In these methods, since yeast can be used at a high concentration, the brewing period can be shortened.
However, the problem inherent in brewing with high yeast concentration, that is, the produced fermentation liquor having a high diacetyl concentration, cannot be escaped, and therefore it is necessary to age the fermentation liquor for a long period of time. Therefore, commercialization is hindered.

On the other hand, in a high yeast concentration brewing method using immobilized yeast or the like, the production of diacetyls is suppressed by adopting fermentation conditions (eg, anaerobic fermentation, low temperature fermentation, etc.) that do not substantially involve yeast growth. Has been proposed [EBC Congress, Proc., 331 (1985)]. However, these methods require a step for making the wort anaerobic.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of producing alcoholic beverages having a stable flavor in a short period of time by suppressing the production of diacetyls as much as possible.

[0007]

[Means for Solving the Problems] That is, the present invention provides a method for producing alcoholic beverages using immobilized yeast, characterized in that the immobilized yeasts whose surface is coated with gel are used. Regarding

The yeast used in the present invention may be any yeast as long as it can metabolize a brewing raw material liquid to produce ethyl alcohol, carbon dioxide and the like, and specific examples thereof include Saccharomyces cerevisiae and Saccharomyces ubalm.

Yeast is immobilized by a conventional method. In the present invention, it is necessary to further coat the surface of the yeast with a gel so that the immobilized yeast is anaerobic. Specifically, by covering the carrier on which the yeast is immobilized with a layer of gel, the yeast inside becomes anaerobic and the production of diacetyls can be suppressed.

The production of such double-immobilized yeast has already been disclosed in JP-A-64-67189. Specifically, there is a method of forming a gel layer by immersing a gel on which yeast is immobilized in an aqueous solution of a substance having a gelling ability, and introducing the gel into a gelling agent, but the following method is preferable. It is preferable to use the double-immobilized yeast according to. That is, a mixed suspension of yeast and an aqueous solution of a substance having a gelling ability was added from the inner tube of the double-tube nozzle, and an aqueous solution of a substance having a gelling ability was simultaneously dropped from the outer tube into the gelling agent to gel It is obtained by forming another gel layer on the exterior of a gel on which yeast is immobilized.

As the substance having gelling ability used for preparing the double-immobilized yeast, any known substance can be arbitrarily used, and examples thereof include sodium alginate, pectin, chitosan, carrageenan, agar and gelatin. . Further, a known substance may be used as the gelling agent,
For example, when the substance having gelling ability is sodium alginate, there are substances that generate soluble polyvalent cations such as calcium chloride, strontium chloride, barium chloride, aluminum chloride and iron chloride (divalent and trivalent). In the case of pectin, calcium chloride, strontium chloride, barium chloride, aluminum chloride, iron chloride (divalent, 3
Aqueous solution such as sodium chloride, magnesium chloride, etc., and in the case of chitosan, an aqueous solution of polymerized phosphoric acid such as sodium metaphosphate, sodium hexametaphosphate, sodium polyphosphate or trivalent phosphate such as tripotassium phosphate is used. To be In the case of carrageenan, an aqueous solution of potassium chloride, calcium chloride, ammonium chloride or the like is used, and in the case of agar or gelatin, cooling water, cooling oil or the like is used.

Next, the brewing raw material liquid used for adding and culturing the double-immobilized yeast obtained as described above contains a yeast substrate and is usually a solution or dispersion containing a saccharide. It is a liquid. Specific examples of such a brewing raw material liquid include wort, fruit juice, a known sugar liquid, and a saccharification liquid using grains as a raw material.

In the fermentation according to the present invention, the sterilized brewing raw material liquid is placed in a fermenter containing double-immobilized yeast for 10 to 15 minutes.
Performed under anaerobic conditions at ° C.

[0014]

EXAMPLES The present invention will be described in detail below with reference to examples. Production Example Preparation of Double Immobilized Yeast 100 ml of 2% alginic acid aqueous solution was added from the outer tube of the double tube.
From the inner tube, brewer's yeast (Saccharomyces cerevisiae) 10 ⁶ cel in 100 ml of 2% sodium alginate aqueous solution.
An ls / sodium alginate aqueous solution was added so as to be 1 ml, and a mixed suspension was added thereto, and these were continuously added dropwise to a 0.1 M calcium chloride aqueous solution and left for 1 hour. As a result, a fibrous double-immobilized yeast having a diameter of 2 mm was obtained.

Example The double-immobilized yeast obtained in Production Example was added to wort adjusted to a sugar content of 11 ° P (plateau), and static fermentation was carried out at 13 ° C. for 48 hours. After the fermentation was completed, the total diacetyl (including precursor) concentration produced was measured. The results are shown in Fig. 1. As is clear from the figure, the production of diacetyl was extremely low even during fermentation, and was 0.16 mg / l after the fermentation was completed. Also,
At this time, the ethanol concentration was 3.6% (w / w),
No yeast leakage was observed.

On the other hand, as a control, a fibrous immobilized yeast having a diameter of 2 mm was prepared in the same manner as in the conventional case using only the inner tube, and fermented under the same conditions as above, and the total diacetyl concentration produced was measured. did. The results are shown in Figure 2. As is clear from the figure, a large amount of diacetyl was produced during fermentation, and the concentration after completion of fermentation was 0.7 mg / l. The ethanol concentration at this time was 3.6% (w / w), and the yeast concentration was 1.
0 × 10 ⁶ pieces / ml leaked.

[0017]

INDUSTRIAL APPLICABILITY According to the present invention, in the continuous production of liquor such as beer using immobilized yeast, the production of diacetyls is suppressed and the liquor having a stable flavor is efficiently produced in a short period of time. You can

[Brief description of drawings]

FIG. 1 is a graph showing the total diacetyl concentration, the amount of pseudo extract, and the amount of yeast leakage in the method of the present invention.

FIG. 2 is a graph showing the total diacetyl concentration, the amount of pseudo extract, and the amount of yeast leakage in the control method.

Claims (1)

[Claims] 1. A method for producing alcoholic beverages using an immobilized yeast, wherein the immobilized yeast having a surface coated with a gel is used.