Isolation and Identification of Pediococcus pentosaceus from Cow’s Milk Curd and Its Use in Grape Juices Fermentation

Aims: The study affirms the quality of fermented grape juices with the potential probiotic bacterium Pediococcus pentosaceus, which can perhaps be used in the preparation of probioticated grape juices.

Study Design: Potential probiotic bacterium was isolated from curd prepared by using cow milk and identified as Pediococcus pentosaceus based on 16S rRNA gene sequencing. It was assessed for fermentation of two varieties of grape (white and red) juices.

Place and Duration of Study: The work was carried out in Microbial Biochemistry Laboratory, Department of Biochemistry, S.V. University, Tirupati - 517 502, India; One year.

Methodology: The isolate was identified by 16s rRNA gene sequencing. Both fruit juices were fermented with isolate and Titratable acidity by titration method, Reducing sugars by DNS method, Cell viability by pour plate, TPC by Folin-Ciocalteu method, Antioxidant assay by DPPH method and Antimicrobial activity by Agar well diffusion method.

Results: The fermented red grape juice showed better fermentation characteristics of pH (3.1) and viable bacterial count (6.5 log CFU/mL) than the fermented white grape juice (3.2 and 6.2 Log CFU/mL) at 72 h fermentation. An increased titratable acidity (0.34%) was observed in fermented red grape juice as compared to the fermented white grape juice (0.27%). The fermented grapes juices possessed higher radical scavenging activity as well as phenolics content than their unfermented juices. The agar-well-diffusion method showed that both the fermented juices were able to inhibit the growth of the selected pathogenic bacteria (E. coli MTCC 40 and B. cereus MTCC 6840). Sensory evaluation showed that fermented red grape juice was preferred to other fermented and unfermented grapes juices.

Conclusion: Production of these fermented fruit juices on commercial scale may benefit the consumers, especially those intolerant to lactose and allergic to milk-based products. In addition, fermented fruit products are cholesterol free, low-cost healthy beverages and may provide better nutrition and health to the needy population.