Impact of Aging Microbiome on Metabolic Profile of Natural Aging Huangjiu through Machine Learning

A quality comparison for Xiecun Huangjiu with different aging stages based on chemical profile, aroma composition and microbial succession

The Xiecun Huangjiu (XCHJ), an exemplary representation of North Huangjiu, exhibits a distinct and invigorating aroma predominantly formed during its aging period. In this study, we observed dynamic changes in 16 key aroma compounds by gas chromatography-mass spectrometry (GC-MS) during the aging of XCHJ, with compounds such as phenethylalcohol, isoamylalcohol, benzaldehyde, and ethylbenzoate initially increasing and then decreasing. Ultra-Performance Liquid Chromatography (UPLC) detected nineteen amino acids, with total content ranging from 1901.45 to 3764.45 mg/L. High-throughput sequencing indicated that Pseudomonas, Ochrobactrum, Moesziomyces and Aspergillus et al. were abundant in aged XCHJ. Totally, 4 bacteria and 8 fungi exhibited strong associations with aroma compounds production. Physicochemical properties were primarily interacted with Pseudomonas, Aspergillus, Pseudeurotium, Thermomyces, Bacteroides and Blautia. Furthermore, co-occurrence network analysis highlighted significant interactions between Pantoea, Rhodotorula, Monascus, and amino acids. These findings provide valuable insights for the regulation of aroma in aged XCHJ.