A sustainable approach to phalsa juice processing: ultrasonication for enhanced nutraceuticals and thermosonication for microbial safety

Fruit juices are highly nutritious, and popular drinks but they are susceptible to quality degradation during pasteurization process. Research on non-thermal techniques of retaining fruit juice quality has grown rapidly in recent years. The aim of this study was to investigate how quality metrics of phalsa juice were affected by thermosonication (TS) and ultrasonication (US). Six samples were employed, in which T 0 (control), T 1 (thermal treatment) at 90 °C for 3 min, T 2 -T 3 samples were ultrasonically treated (US) at 37 kHz for 5–10 min (30 °C), and T 4 -T 5 samples were thermosonicated (TS) at 37 kHz for 5–10 min (50–60 °C) to determined their effect on physicochemical, phytochemical, and microbiological characteristics of phalsa juice. Physicochemical and microbial analyses were conducted at refrigerator temperature (4 °C) for 12 days. The results demonstrated that the T 3 sample (US treated) significantly had higher levels of vitamin C (414.57–462.09 mg/100 mL), total flavonoid (654.68–684.73 mg CE/100 mL), and total phenolic (134.83–152.43 mg GAE/100 mL) as well as their total antioxidant capacity (TAC) (589.69–648.44 μg/g) and DPPH (1204.5–1274.8 μg/g AAE) while TSS and TA are slightly affected in all treated samples. The T 5 Sample at 10 min (60 °C) had the highest inactivation of total plate count (2.76 CFU/mL), yeast and mold (2.21 CFU/mL) at 0 day, thus the microbial population was significantly inactivated by thermosonication. All treatments experienced a decrease in pH and TSS values, while titratable acidity increased significantly over a storage period. In comparison to the control group, total plate count, yeast, and mold significantly decreased in all treated group over a period of 12 days. The results of this study imply that US and TS treatments are a potential method for improving juice quality, economical and nutritional advantages of industrial processing for enhancing microbial safety and shelf life.