Late-maturing cooking rice Sensyuraku has excellent properties, equivalent to sake rice, for high-quality sake brewing.

Low protein content and sufficient grain rigidity are desired properties for the rice used in high-quality sake brewing such as Daiginjo-shu (polishing ratio of the rice, less than 50%). Two kinds of rice, sake rice (SR) and cooking rice (CR), have been used for sake brewing. Compared with those of SR, analyses of CR for high-quality sake brewing using highly polished rice have been limited.

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.

Polishing properties of sake rice Koshitanrei for high-quality sake brewing.

The Japanese high-quality sake Daiginjo-shu is made from highly polished rice (polishing ratio, less than 50%). Here we showed that the sake rice Koshitanrei (KOS) has an excellent polishing property. Rice grains of KOS had the same lined white-core region as the sake rice Yamadanishiki (YAM).