Optimization of Fermentation Conditions for a Complex Type of Seeding-watermelon Kiwi Fruit Kvass Beverage by Response Surface Method

Taking seeding-melon and Actinidia arguta as raw materials, the inoculum amount of Lactobacillus plantarum, the fermentation time, the ratio of saccharification solution to the seeding-melon and Actinidia arguta juice and the amount of pectinase were taken as the investigation factors, and the sensory score was the response value, the process development and optimization were by Box-Behnken response surface method. The results showed that the optimum conditions were as follows:The inoculum of Lactobacillus plantarum was 2×10⁷ CFU/mL, the fermentation time was 12 h, the ratio of saccharification solution to the seeding-melon and Actinidia arguta juice was 0.97:1 (v/v), and the amount of pectinase was 15 mg/100 g, under these conditions, the sensory scores was (94.0±0.2) scores.The finish beverage had a light yellow-green color, pure flavor, moderate sweet and sour, clear and no precipitation, and had the fruity flavor of seeding-watermelon and kiwi fruit. And mixed with the flavor produced by fermentation, the taste was fresh and delicate, and the aftertaste was refreshing.