Effect of Water Activity on Flavor and Microbial Community of Dehydrated Chives during Storage

The volatile compounds and microbial community composition of dehydrated chives stored under different water activity (a_w) conditions for 50 days were investigated in the present study, and the correlation between them was also analyzed. The data showed that the bacterial community diversity in dehydrated chives was significantly increased after storage (P < 0.05), and the bacterial community structure was changed noticeably. The relative abundance of the families Leuconostocaceae and Enterobacteriaceae, and the genera Weissella, Erwinia, Rosenbergiella and Ewingella were significantly decreased, and the relative abundance of 17 families including Micrococcaceae, Microbacteriaceae, and Nocardiaceae, and 20 genera including Kocuria, Streptococcus, and Bacillus were significantly higher in dehydrated chive samples stored at the highest a_w of 0.84 than at other a_w levels. After 50 days of storage, the types and relative contents of volatile sulfide components were decreased, while those of volatile hydrocarbons were elevated. The relative abundance of Kocuria, Streptococcus and Bacillus were closely associated with the contents of various volatile compounds. The present study revealed that a_w has an important impact on the storage characteristics and quality of dehydrated chives. This finding may be helpful for quality maintenance and shelf-life extension of dehydrated chives during storage.