Study On Pumpkin And Pitaya Juice Fermented By Probiotics

These experiments choose the pumpkin and pitaya as raw materials, with Lactobacilluscasei and Lactobacillus plantarum as strains. The main research was about the characteristicsof the lactobacillus in fermented pumpkin juice and pitaya juice, and the stability in coldstorage conditions. The analysis will provide theoretical basis and basic parameters forvegetable and fruit juice drinks fermented by probiotics. The results are as follows:The fermentation of pumpkin juice and pitaya juice with Lactobacillus plantarum wasstudied. After48h, viable cell counts were3.30×10~8cfu/mL and1.85×10~9cfu/mL. For aciditywere99.35°T and99.63°T, and pH value dropped to3.62and3.72, respectively.The fermentation of pumpkin juice and pitaya juice with Lactobacillus casei was studied.After48h, viable cell counts were1.89×10~9cfu/mL and2.10×10~9cfu/mL. For acidity were126.26°T and141.43°T, and pH value dropped to3.50, respectively. During the fermentationprocess of pitaya juice with Lactobacillus casei or Lactobacillus plantarum, pH value did notfall but rise. This abnormal situation suggests that pitaya juice contains the composition of thealkaline substances and degradated.Single fermentation and the fermentation of complex strains were compared. Whether itis in the pumpkin juice or the pitaya juice, although not existing significant synergistic, atleast not antagonistic. With pumpkin juice and pitaya juice as the substrate, the final viablecell counts were2.30×10~9cfu/mL and3.79×10~9cfu/mL, pH value of3.36and3.50, the acidityof133.38°T and142.33°T, after the composite fermentation of48h.The stability of fermented fruit and vegetable juices in cold storage was studied,including pH, acidity, and the viable cell counts. The results showed that: the viable cellcounts of Lactobacillus plantarum and Lactobacillus casei remained stable, slow metabolism.In terms of strains, the acidity value change of fermented fruit and vegetable juice withLactobacillus casei was more obvious than with Lactobacillus plantarum in cold storage.