Physicochemical Characterization, Antioxidant Activity and Aroma Analysis of Goat's Milk Wine Fermented with Mixed Lactic Acid Bacteria and Yeasts

In this study, goat's milk was fermented by Saccharomyces cerevisiae mixed with six strains of Lactobacillus, respectively, to produce goat's milk wine, and goat’s milk fermented with Saccharomyces cerevisiae was used as the control. Changes in the physicochemical properties, antioxidant activity and volatile compounds of goat's milk during fermentation process were studied. The results showed that the addition of lactic acid bacteria accelerated the decrease in total sugar content of goat's milk wine at the early stage of fermentation compared to the control, and the total sugar content of goat's milk wine fermented with Lactobacillus fermentum decreased significantly from 469.46 g/L to 210.41 g/L after 1 d of fermentation. The addition of lactic acid bacteria resulted in a significant increase in the scavenging capacity of ABTS⁺ radical and hydroxyl radical in fermented goat's milk wine (P<0.05), especially for Lactobacillus acidophilus, increasing ABTS⁺ radical scavenging capacity and hydroxyl radical scavenging capacity by 9.94% and 37.75%, respectively, compared to the control. In addition, the content of volatile compounds in goat's milk wine fermented with Lactobacillus acidophilus was the highest (2688.30 mg/L). The mixed fermentation of lactic acid bacteria and yeast reduced the content of alcohols and acids, reduced the odor of goat's milk wine, and generated new volatile substances such as cyclopentanone, ethyl lactate and ethyl hexanoate, endowing goat's milk wine new aroma characteristics. The mixed fermentation of Lactobacillus acidophilus and Saccharomyces cerevisiae not only innovated the brewing process of goat's milk wine, but also provided a theoretical basis for the deodorization of goat's milk wine.