Abstract: Soybean paste intensive fermented with mixed koji of Aspergillus oryzae (Pi-niang M003) and Monascus purpureus (PM001) was analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry, principal component analysis system to compare the volatile flavor components in different mixed fermented soybean paste, and Illumina Miseq sequencing technology was used to analyze the microbial structure in different soybean paste fermentation process, and the correlation between the main microorganisms and the key flavor substances was analyzed by correlation analysis. The results showed that the intensive fermentation of Monascus has a significant effect on the flavor substances and microbial structure of soybean paste during fermentation; Spearman correlation analysis of dominant genera and flavor substance components found that many flavor substances in soybean paste were significantly positively correlated with dominant genera, and Monascus intensive fermented soybean paste had more abundant flavor substance types and contents, among which Monascus intensive fermented soybean paste C had better flavor quality. The results indicate that Monascus intensive fermented soybean paste can significantly improve the flavor quality of soybean paste, and provide data reference for the improvement of soybean paste flavor quality.

Key words: monascus, intensive fermentation, volatile flavor components, microbial structure