Analysis of flavor-related compounds in fermented persimmon beverages stored at different temperatures

Storage temperature plays a very important role in the flavor development of fermented beverages. In this study, fermented persimmon beverage was stored for one year to study the changes in flavor-related compounds during storage at different temperatures. Fresh persimmon beverage and fermented beverages stored at 10, 20, and 30 °C had different tastes, distinguished by electronic tongue (ET). The fermented beverage was sweet when stored at 10 °C and salty when stored at 20 °C or above. A total of 658 nonvolatile metabolites were identified, among which quercetin and epicatechin were detected by a liquid chromatography-mass spectrometry (LC-MS) based metabolomics approach from four fermented beverage samples. The volatile compounds in the beverages were determined by headspace solid phase microextraction, combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) and gas phase-ion migration spectroscopy (GC-IMS), respectively showing totals of 47 and 69 compounds in the four beverage samples. As detected by both methods, ethyl acetate, ethyl hexanoate, ethyl octanoate, ethanol, and acetic acid were all found in beverages stored at different temperatures and the results showed that a higher storage temperature resulted an increase in the number of volatile compounds in the beverage. However, fermented persimmon beverage stored at low temperatures had a better taste and flavor characteristics.