Method for screening low-yield diacetyl beer yeast

Abstract

The invention belongs to a method for screening low-yield diacetyl beer yeast. D-valine (D-Val) has a certain inhibition function on yeast growth. According to the method, 13 DEG P wort containing D-Val at certain concentration is adopted to domesticate yeast under appropriate conditions, strains which are sensitive to D-Val are screened from yeast paste, fermentation experiment is implemented to detect the diacetyl content of a sensitive strain, and the result shows that the reduction rate of diacetyl can reach 34.08%. The method is simple to operate and accurate and stable in result, and technical support is provided for research and development of the beer industry and high-quality beer production.

Description

technical field

[0001] The invention relates to a screening method for brewer's yeast with low diacetyl production. Background technique

[0002] Diketones are the main source of "raw wine taste" in beer and one of the restrictive indicators of beer maturity, mainly including diacetyl and pentanedione, of which diacetyl is particularly important. Diacetyl is a volatile and highly irritating compound, which is the precursor of many aroma substances, and is also the main aroma substance of dairy products such as butter and cheese. The threshold of diacetyl in beer is between 0.1-0.2mg / L. When the content is >0.5mg / L, it has an unpleasant and irritating smell similar to the smell of rotten rice; when the content is >0.2mg / L, it has a burnt malt smell . Excellent light beer diacetyl should be controlled below 0.06mg / L. Screening low-yield diacetyl beer yeast can not only effectively reduce diacetyl content in the main fermentation part of beer fermentation, but also lay...