Optimization of Fermentation Process of Aronia melanocarpa Fruit Juice by Lactobacillus plantarum

The Aronia melanocarpa was taken as material, the Aronia melanocarpa juice was fermented using Lactobacillus plantarum C8-1 bacteria in order to improve its nutritional value and its fruity flavor. The conditions of Aronia melanocarpa fruit juice fermentation by Lactobacillus plantarum were optimized by single factor test and orthogonal test. Bacteria inoculation, fermentation temperature, time and material into water ratio were considered as influencing factors and total acid content indicated the results of orthogonal experiment. The results showed that, the optimal fermentation conditions were:9lg CFU/mL for Lactobacillus plantarum concentration, fermentation temperatur 35℃ fermentation time 22 h, material into water ratio 1:3 (v:v).Under those conditions, the total acid content could reach 6.60 mg/mL. The physicochemical properties of the fermented Aronia juice showed that the total phenolics and acid content increased respectively to 10.51%, 74.60% after fermentation. The results of color study showed that the fermentation enhanced the brightness, red color and yellow color of Aronia fruit. Antioxidant experiments showed that the free radical scavenging ability of DPPH, the scavenging activity of OH and the total reducing power were significantly higher than those of freshly squeezed Aronia fruit juice (p<0.01). The sensory score was significantly higher than that of fresh juice. The results showed that Lactobacillus plantarum C8-1 could perform normal growth in the Aronia juice, and fermentation could improve the quality and antioxidant activities of the Aronia juice.