宣城地区中温大曲品质及微生物多样性解析OA

This study first analyzed the physicochemical properties and sensory qualities of Xuancheng medium-temperature Daqu u-sing conventional physicochemical methods and bionanotechnology.Subsequently,this study assessed its microbial diversity through PacBio SMRT sequencing and pure culture techniques,exploring the correlation between dominant microorganisms and the physicochemical prop-erties and sensory qualities.The physicochemical analysis indicated that the measured values of the physicochemical indexes for Xuancheng medium-temperature Daqu met the standards;however,the coefficients of variation for six indexes,namely,free water,amino acid nitro-gen,saccharification power,esterification power,fermentation power,and liquefaction power,were all greater than 15％.Sensory quality analysis revealed that the flavor component contained higher levels of organic sulfides,terpenes,and ethanol,while the taste component exhibited increased sourness and richness(aftertaste of umami).PacBio SMRT sequencing results identified Delftia tsuruhatensis as the dominant bacterial species,with an average relative abundance of 17.31％,and Thermoascus aurantiacus as the dominant fungal species,with an average relative abundance of 33.05％.Additionally,Wickerhamomyces anomalus contributed an average relative abundance of 25.44％.Correlation analysis suggested that bacterial taxa may be more closely associated with the relationship between the physicochemi-cal properties and sensory qualities of the medium-temperature Daqu than fungal taxa.The pure culture results indicated that the culturable bacteria were primarily composed of Pediococcus pentosaceus,Bacillus licheniformis,and B.siamensis,accounting for 41.94％,17.74％,and 16.13％,respectively.This study enhances the understanding of the physicochemical properties,organoleptic quality,and microbial diversity of medium-temperature Daqu.