Microbial Diversity and Changes in Flavor Compounds During the Fermentation of Vegetables: A Review

Fresh vegetables are prone to spoilage due to their abundant nutritional content and adequate water, which favor microbial growth and enzymatic activity. These factors contribute to rapid quality deterioration and a limited shelf life. Fermentation is a time-honored food processing technique and a cornerstone of traditional preservation methods. Fermented vegetables are pickled food products obtained through controlled environmental conditions and microbial fermentation processes. During the fermentation process, microorganisms play a crucial role in determining the final quality and flavor of the vegetables. Additionally, vegetables themselves produce a range of volatile and non-volatile compounds that contribute to characteristic flavors such as sourness, umami, and richness. Fermented vegetables with unique flavors can promote appetite and digestion, and they are highly valued by most consumers. Therefore, this review examines the mechanisms underlying the fermentation process, the influence of microbial diversity, and the changes in flavor compounds during vegetable fermentation. It also explores the interrelationship between microbial activity and flavor development. Furthermore, the review highlights current challenges and future research directions in vegetable fermentation, providing a theoretical basis for improving the quality of fermented vegetables.