Correlations between microbes and metabolites of hulless barley wines fermented with varieties of hulless barley and different starters

Hulless barley wine has been widely researched for its high nutritional values and unique flavor. However, the different varieties of hulless barley and a variety of local characteristic starter in the Qinghai-Tibet Plateau, which make the styles of hulless barley wine in different. In this study, the microbial community compositions of representative starters were investigated. Meanwhile, the physicochemical indexes, sensory analysis, volatile flavor compounds and free amino acids of different wines fermented with varieties of hulless barley and different starters were determined, respectively. In addition, the correlations between microbes and metabolomics were explored. The results showed that there were differences between fungal communities and between bacterial in differences starters. The influence of different starters on the quality of hulless barley wine was greater than that of hulless barley varieties. 16 microbial generas Acetobacter, Weissella, Chloroplast, Bacillus, Leuconostoc, Methylobacterium, Rhizopus, Aspergillus, Pichia, Hyphopichia, Wallemia, Xeromyces, Gibberella, Alternaria, Curvularia and Microdochium were discovered to be positive correlated with metabolites by Spearman's correlation analysis. These findings may indicate the key microorganisms of volatile substances and free amino acids in hulless barley wine, help to select hulless barley varieties and control the microorganisms of starter, and improve the quality of hulless barley wine.