The variations analysis of volatile flavors and microbial communities during fermentation of Chinese Taizhou pickle, and the isolation and identification of fermentative microorganisms

Abstract

Taizhou pickle is a special local Chinese fermented vegetable product that consumers highly regarded for its distinctive flavor. This study revealed a significant reduction in acidity during fermentation. Volatile compounds and microbial communities in Taizhou pickles during fermentation were investigated using gas chromatography-mass spectrometry (GC-MS) and high-throughput sequencing. A total of 79 volatile compounds were identified from pickles. In addition to essential esters, the pickle also contained flavor compounds such as alcohols, acids and sulfur compounds. For instance, while the levels of isothiocyanates gradually decreased, the content of esters and sulfur compounds such as butyl butyrate, ethyl caproate, ethyl butyrate and dimethyl disulfide gradually increased. The predominant fungal genera identified in the pickles were Candida , Mucor and Debaryomyces . Lactobacillus , Pseudomonas , Alcaligenes and Caproiciproducens were identified as the main bacterial genera. Additionally, strain identification revealed that the most important fermentative lactic acid bacterium may be Loigolactobacillus coryniformis . This study helps to understand the quality changes of pickles during the fermentation process as well as to understand better the role of microorganisms in the formation of flavor, and provides a scientific basis for the industrialization of Taizhou pickles. • A detailed characterization of the pickle’s microbial diversity was described. • The key fermentative microorganisms were isolated and identified. • Relation of microbial community and flavors in Taizhou pickle was first reported. • L. coryniformis plays a crucial role in the flavor development of Taizhou pickle.