Optimization of process and quality characteristics of pea milk fermentation by lactic acid bacteria

In order to develop new nutritional pea milk, Lactobacillus plantarum was used in the fermentation process. The effects of fermentation time, temperature, inoculated amount and pea flour addition on the number of viable bacteria in pea fermented milk were studied through single factor experiment. The results indicated that the optimal conditions were: fermentation temperature of 36 ℃, inoculated amount of lactic acid bacteria of 0.10%, additive amount of pea powder of 5.83%, fermentation time for 24 h. The interaction between pea powder addition and fermentation temperature, fermentation temperature and time had significantly influences on the number of viable bacteria. The logarithm of viable bacteria counts under the optimal fermentation conditions was 9.05 CFU/mL, the total phenolic content was 281.77 mg/L, the total sugar content was 86.01 mg/mL, the starch content was 21.94 mg/g, and the protein content was 0.11 mg/g. Compared with pre-fermentation, the antioxidant activity of pea milk was significantly enhanced after fermentation, and the DPPH clearance could reach 66.83%. The total sugar, total phenolic content, number of viable bacteria, antioxidant activity and starch content of pea fermented milk were higher than those of soybean fermented milk. The texture of pea fermented milk was determined by texture analyzer, and the results showed that the adhesion, cohesion, hardness, elasticity and chewiness of pea fermented milk were significantly improved. Pea fermented milk fermented for 24 h showed the highest sensory score. The fermentation by plant lactic acid bacteria can improve the nutritional composition and quality characteristics of pea milk, and the research results provide a new way for the development and utilization of pea.