Investigating the role of primary fungi in Huangjiu fermentation: Insights from flavor orientation and synthetic microbiomes

Abstract

Huangjiu, a traditional alcoholic beverage, presents a complex fermentation ecosystem primarily influenced by specific fungal species. This study utilized a culture-dependent approach and amplicon sequencing to explore fungal community succession during Huangjiu fermentation. Key fungi identified include Saccharomyces cerevisiae, Aspergillus species (flavus, oryzae, niger), Saccharomycopsis fibuligera, Thermomyces lanuginosus, Rhizopus arrhizus, Issatchenkia orientalis, Wickerhamomyces anomalus, and Diutina rugosa. Employing a synthetic microbiome, we developed a dual-strain fermentation system to evaluate the impact of these fungi on Huangjiu's organoleptic properties. Introduction of these fungi significantly altered the flavor profile, enhancing 23 volatile organic compounds (VOCs), with S. fibuligera notably increasing nine distinct VOCs. While molds contributed to bitterness by increasing bitter amino acids, S. fibuligera effectively mitigated these components, enhancing the beverage's alcohol body, smoothness, and balance. These findings provide crucial insights for optimizing Huangjiu fermentation to improve its quality and appeal.