Optimization of Brewing Technology of Hovenia acerba-Sorghum Co-fermented Distilled Liquor and Its Characteristic Flavor Substances and Antioxidant Activity in Vitro

A new type of distilled liquor was brewed using Hovenia acerba and sorghum as raw materials, medium-temperature Daqu as starter. Fermentation parameters were optimized by single factors experiment and orthogonal test. The flavor components were detected and analyzed by headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and odor activity threshold (OAV). And the antioxidant capacity in vitro was evaluated. The results showed that the optimal preparation conditions were determined as follows: Addition of Hovenia acerba was 20% and Daqu was 15%, and fermentation time was 35 d. Under the optimized conditions, the sensory score of 93.91, the product yield of 40.21%. A total of 48 flavor substances were identified in the liquor prepared under the optimized conditions, of which 20 were OAV>1. Ethyl butyrate, ethyl octanate, ethyl hexanoate ethyl and guaiacol were considered as the characteristic flavor substances of the Hovenia acerba-sorghum co-fermented distilled liquor. Compared with pure sorghum distilled liquor, phenylethanol, 2,3-butanadiol, 9-ethyl decanolate, 10-bromodecanoic acid ethyl ester and other volatile components were special in the Hovenia acerba-sorghum co-fermented distilled liquor. In addition, the total phenol content, DPPH and ABTS free radical scavenging ability, and total reducing power of the Hovenia acerba-sorghum co-fermented distilled liquor were higher than the pure sorghum distilled liquor. This study provides a scientific reference for the industrial production of liquor and a new idea for the development of new health distilled spirits.