Effect of starter on metabolites in Japanese alcoholic beverage sake made from the sake rice .

In sake brewing, the steamed rice is used in 2 ways, added to sake-mash and making rice. Rice- is made from the steamed rice by using starter, and its quality is an important determinant of the aroma/taste of sake. The sake rice (KOS) was developed in Niigata Prefecture by crossing 2 sake rice varieties, and .

Analysis of metabolites in Japanese alcoholic beverage sake made from the sake rice .

In sake brewing, the steamed rice is used in two ways, added to sake-mash (as ) and making . The rice is an important determinant for the quality of sake, as the metabolites in sake affect its taste/aroma. The sake rice (KOS) was developed in Niigata Prefecture by genetically crossing two sake rice, and .

Phenotypic Diagnosis of Lineage and Differentiation During Sake Yeast Breeding.

Sake yeast was developed exclusively in Japan. Its diversification during breeding remains largely uncharacterized. To evaluate the breeding processes of the sake lineage, we thoroughly investigated the phenotypes and differentiation of 27 sake yeast strains using high-dimensional, single-cell, morphological phenotyping.

Evaluation of the comprehensive palatability of Japanese sake paired with dishes by multiple regression analysis based on subdomains.

Many factors contribute to palatability. In order to evaluate the palatability of Japanese alcohol sake paired with certain dishes by integrating multiple factors, here we applied an evaluation method previously reported for palatability of cheese by multiple regression analysis based on 3 subdomain factors (rewarding, cultural, and informational). We asked 94 Japanese participants/subjects to evaluate the palatability of sake (1st evaluation/E1 for the first cup, 2nd/E2 and 3rd/E3 for the palatability with aftertaste/afterglow of certain dishes) and to respond to a questionnaire related to 3 subdomains.

Identification of a mutation causing a defective spindle assembly checkpoint in high ethyl caproate-producing sake yeast strain K1801.

In high-quality sake brewing, the cerulenin-resistant sake yeast K1801 with high ethyl caproate-producing ability has been used widely; however, K1801 has a defective spindle assembly checkpoint (SAC). To identify the mutation causing this defect, we first searched for sake yeasts with a SAC-defect like K1801 and found that K13 had such a defect. Then, we searched for a common SNP in only K1801 and K13 by examining 15 checkpoint-related genes in 23 sake yeasts, and found 1 mutation, R48P of Cdc55, the PP2A regulatory B subunit that is important for the SAC.

Isolation of a spontaneous cerulenin-resistant sake yeast with both high ethyl caproate-producing ability and normal checkpoint integrity.

In the brewing of high-quality sake such as Daiginjo-shu, the cerulenin-resistant sake yeast strains with high producing ability to the flavor component ethyl caproate have been used widely. Genetic stability of sake yeast would be important for the maintenance of both fermentation properties of yeast and quality of sake. In eukaryotes, checkpoint mechanisms ensure genetic stability.

Isolation of a non-urea-producing sake yeast strain carrying a discriminable molecular marker.

In the fermentation industry, the traceability of microorganisms during the process is important to ensure safety and efficacy. Ethyl carbamate, a group-2A carcinogen, is produced from ethanol and urea during the storage of food/alcoholic beverages. We isolated non-urea-producing sake yeast car1 mutants carrying a discriminable molecular marker, and demonstrated, by the use of PCR assays, that these mutants are useful for traceability analysis and identification during the sake brewing process.