Dynamic changes of quality characteristics during fermentation of orange-fleshed sweet potato alcoholic beverage

Abstract

Orange-fleshed sweet potato (OFSP) is a high-yield sweet potato widely planted in China. Through fermentation, the flavor and nutritional value of OFSP can be preserved, obtain a highly nutritious alcoholic beverage. To elucidate the quality transformations of OFSP alcoholic beverage (OFSPAB) throughout the fermentation process, the dynamic variations in various key indices were monitored by high-performance liquid chromatography (HPLC) and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS/SPME-GC/MS) technology. The results showed, after fermentation, the OFSPAB beverage exhibited an alcohol content of 10.2 %vol, a total phenol content of 458.67 mg/L, a total flavonoids content of 230.42 mg/L, and an in vitro free radical scavenging rate exceeding 50%. Thirteen phenolic compounds were identified, and the total content increased from 17.75 mg/L to 91.45 mg/L. A total of 77 volatile compounds were identified. The main compounds in raw materials were alcohols and aldehydes, such as heptanol, decanal. After fermentation, a large number of esters, including ethyl acetate, propyl lactate, were produced, which enriched the aroma of OFSPAB. The results will provide a novel perspective for the deep processing of OFSP and establishes a theoretical foundation for the development of OFSPAB.