Physicochemical, Aroma Compounds, Microbial Community, and Antioxidant Capacity of Huangjiu-Based Functional Liqueur Fermented with Edible Herbs

A functional Huangjiu-based liqueur (called by Lujiu in China), a type of Chinese rice wine, was developed by incorporating Chinese gall leaven, as a medicinal–edible homologous ingredient, into the fermentation process to enhance its bioactivity. The physicochemical properties and enzymatic activities were investigated and found that supplementation with 2% (v/v) Chinese gall leaven optimized fermentation efficiency and substrate utilization. The co-fermentation significantly elevated the concentrations of bioactive compounds and improved antioxidant capacity, particularly free radical scavenging activity. Compared to traditional Chinese rice wine, the supplemented variant exhibited markedly higher levels of malic acid and phenolic acids. GC-MS analysis identified 85 and 84 volatile flavor compounds in the two supplemented variants, respectively, exceeding the 70 compounds detected in traditional Huangjiu. GC-IMS further revealed significant enrichment of key alcohols (e.g., 3-methyl-1-butanol, 2-methyl-1-propanol) and aldehydes (e.g., propanal, acetaldehyde) in the supplemented group. Microbial community analysis indicated distinct shifts, with increased relative abundances of Pediococcus, Lactiplantibacillus, Aspergillus, and Saccharomyces in the Chinese gall leaven-supplemented fermentation. These results suggest that the native microflora and enzymatic systems of Chinese gall leaven could enhance microbial metabolism and fermentation efficiency, thus contributing to the unique characteristics of rice wine and providing a novel strategy for functional Huangjiu-based liqueur production.