Fermentation Process Optimization and Cold Storage Quality Change of Prunus Americana Juice Fermented by Probiotic

To provide solutions for the development of the Prunus Americana probiotics drinks, we explored the suitable fermentation strains, process parameters and storage conditions. The sensory evaluation and pH change of probiotic beverage fermented by Lactobacillus acidophilus, Lactobacillus plantarum, Streptococcus thermophilus and their combination were studied to determine the appropriate combination of fermentation strains, and the suitable inoculum amount, fermentation temperature and fermentation time were optimized. In addition, the changes of titratable acid, pH value, soluble solid content, reducing sugar content and the total number of viable colonies of probiotics beverage under 4 ℃ cold storage were studied to obtain the appropriate storage conditions. The results showed that the 1:1:1 mixed strain was more suitable for fermentation, and the optimum fermentation conditions were as follows: fermentation temperature 25 ℃, fermentation time 44 h, inoculation amount 0.7‰.Validation experiments showed that the sensory score was as high as 9.2. The titratable acid, pH value, soluble solid content and reducing sugar content of the probiotic beverage kept stable after 30 days of cold storage at 4 ℃, and the total number of viable colonies reached 8.6×10⁷ CFU· mL⁻¹ after 20 days and 2.0×10⁶ CFU·mL⁻¹ after 30 days, which met the requirements of active lactic acid bacteria beverage. All these indicate that it is feasible to develop probiotic beverage with Prunus Americana as raw material.