JPH0241318B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for brewing wine, and more particularly to a method for brewing must wine using must as a raw material. Must is concentrated grape juice, which is the raw material for winemaking, and has an alcohol concentration of 1% or more. When brewing wine using must as raw material, the must is diluted to adjust the concentration and then fermented.
Compared to normal fermentation of raw grape juice, fermentation tends to be slow, and the resulting wine is known to have an unpleasant flavor called must odor. This phenomenon poses a significant obstacle to winemaking using must as a raw material. It has been pointed out that one of the reasons for this is that must generally has a high sulfite content, and countermeasures focusing on sulfite, such as selection and breeding of yeast with strong sulfite tolerance and attempts to reduce sulfite from must, have been considered. . Furthermore, a method has been proposed in which fermentation inhibitors are reduced or yeast nutrients are supplied by diluting the must and mixing it with other raw materials. However, these methods have drawbacks such as requiring complicated steps, lacking in practicality from an economic standpoint, not being sufficiently effective, or resulting in poor quality wine. An object of the present invention is to provide a must wine brewing method that eliminates these drawbacks. The present invention is a must wine brewing method that is characterized by fermenting must under reduced pressure either continuously or intermittently. When producing wine by fermenting ordinary grape juice, 1 to 3% of yeast mash is added to the amount of fruit mash (National Tax Agency Prescribed Analysis Method Commentary, 3rd revised edition, vol.
(See page 55). In practice, 1% of the mash is sufficient (Dittrich; Mikrobiologie des
Weines, p. 162), and sometimes fermentation is carried out without adding mash at all. In this way, when raw grape juice is used as a raw material, it is rich in nutrients, yeast grows vigorously, and the maximum bacterial concentration easily reaches several hundred million cells/ml. However, when must is used as a raw material, good fermentation cannot be expected as described above.
Therefore, in the present invention, in order to promote fermentation of must, fermentation is carried out under reduced pressure continuously or intermittently. The degree to which the pressure should be reduced during fermentation of the must is 0.3 from the minute vacuum suction that hardly appears on the gauge.
A reduced pressure of up to Kg/cm ² is sufficient. From the point of view of energy saving, it is preferable to set it to 0.2 Kg/cm ² or less. There is no particular restriction on the time when the pressure should be reduced, but it is effective to promote fermentation during the yeast growth period or the first half of fermentation. Furthermore, when fermenting must, if the mash is added to the mash at a concentration of 4% or more, the initial concentration of bacteria in the fermentation liquid is expected to reach 100 million cells/ml. This mash is preferably 10 to 30% of the sake mash.
%. In the present invention, fermentation is carried out under reduced pressure continuously or intermittently, so that undesirable aroma components produced as by-products during fermentation can be quickly volatilized. Furthermore, during must fermentation, the presence of carbon dioxide is undesirable as it inhibits the growth of yeast and affects the balance of yeast products; This will remove the carbon dioxide gas that is produced, which will promote the growth of yeast. As described above, according to the method of the present invention, there is no need for pretreatment such as removing fermentation inhibiting factors from the must, which is the raw material, and there is no need to select and use special yeast with strong sulfite properties. wine can be brewed. The method of the present invention is a simple method, the fermentation period can be shortened, and the flavor of the wine is improved, so it can be effectively used in wine production. Next, examples of the present invention will be shown. Example 1 Must adjusted fruit juice (21.2゜BX, acidity 0.6%) 750ml
35 ml (equivalent to 4.7% of the moromi) of sake mash (Satsucharomyces cerevisiae OC-2 strain was inoculated into Koshu grape juice, cultured at 20°C, and a fermented liquid with vigorous growth) was added to the mixture. Thereafter, fermentation was carried out by continuously suctioning -30 cm/Hg using a small vacuum pump. For comparison, static fermentation at normal pressure was also conducted (Comparative Example 1). However, 15 ml (equivalent to 2% of the moromi) of sake mash was added. Fermentation was discontinued after 18 days, and the amount of reducing sugar and the amount of yeast recovered (centrifugation sediment) at the end of fermentation were examined. The results of the fermentation test are shown in Table 1. In addition, the progress of fermentation was monitored by the carbon dioxide gas reduction method. FIG. 1 is a graph showing the fermentation progress of must.

[Table] As is clear from Table 1 and FIG. 1, it can be seen that according to the present invention, fermentation is promoted and the fermentation period can be shortened.

[Brief explanation of drawings]

FIG. 1 is a graph showing the fermentation progress of must.

Claims (1)

[Claims] 1. A must wine brewing method characterized by fermenting must under reduced pressure either continuously or intermittently.