Abstract:
Zhenjiang aromatic vinegar, one of the most renowned traditional Chinese cereal vinegars, is favored by consumers for its elegant and complex aroma. Aging is a critical process that significantly shapes its final flavor and quality. However, the succession of microbial communities and their impact on volatile flavor compounds during aging remain unclear. This study aimed to systematically investigate the dynamic changes and correlation analysis of volatile flavor compounds and microbial communities of Zhenjiang aromatic vinegar during aging. A total of 808 volatile flavor compounds were identified, and their contents differed after aging. The total content of volatile flavor compounds peaked at Y3, while the content of pyrans was highest at Y10. Twelve compounds contributed significantly to the overall aroma of Zhenjiang aromatic vinegar. With extended aging, the OAV of compounds like 2,4,5-trimethyloxazole increased, whereas those of others, such as
α,
α,4-trimethylcyclohex-3-ene-1-methylmercaptan decreased. Aging enhanced the unique aromatic properties and improved the flavor of Zhenjiang aromatic vinegar. High-throughput sequencing analysis revealed that Proteobacteria and Actinobacteriota were the dominant bacterial phyla during aging, with Firmicutes abundance peaking at Y3. Key bacterial genera in the fermentation stage, such as
Pseudomonas, remained abundant during aging.
Parengyodontium was the predominant fungal genus, while
Meyerozyma exhibited phased changes during aging.
Aspergillus and
Penicillium emerged after a decrease in total acidity at Y5. Correlation analysis indicated that
Aspergillus,
Penicillium and
Pseudomonas were significantly associated with approximately 75% of the key aroma compounds. Fungi might exert a greater influence on key aroma compounds than bacteria during aging. The findings deepen the understanding of flavor compounds and microbial communities in aged Zhenjiang aromatic vinegar, providing a theoretical basis for the optimization and quality control of aging.