Study on the nutritional characteristics and antioxidant activity of dealcoholized sequentially fermented apple juice with Saccharomyces cerevisiae and Lactobacillus plantarum fermentation

For the preparation of non-alcoholic fermented apple juice products with high antioxidant activity, we evaluated the physicochemical indicators, functional components, aroma and antioxidant activity of products at different stages of Saccharomyces cerevisiae fermentation, dealcoholization, and Lactobacillus plantarum sequential fermentation. After S. cerevisiae fermentation, the total sugar was reduced by 7.46 g/100 mL and the ethanol reached 6.56% (v/v), which decreased to less than 0.50% (v/v) after dealcoholization. After L. plantarum fermentation, the viable count reached 4.26 x 108 CFU/mL and flavonoids increased; vitamin C and B6 levels peaked at 1.97 and 1.17 mg/100 mL respectively. Fermented by L. plantarum after dealcoholized, new volatiles were produced (propanol, citronellol, ethyl lactate and hexyl butyrate), ketones and acids were enriched; antioxidant activity was improved and had the highest free radical scavenging rate. The sequential fermentation of apple juice with S. cerevisiae, dealcoholization, and L. plantarum enriched its nutritional properties and antioxidant activity.