Impact of pulsed light treatment on achieving microbial safety, enzymatic stability, and shelf life extension of dragon fruit juice

Abstract

Due to microbial and enzymatic spoilage, dragon fruit juice has a limited shelf life. This study examines the shelf life of dragon fruit juice treated with thermal and pulsed light (PL) processing and stored at 4°C. The thermal treatment at 95°C/3 min and PL treatment at 1.4 J cm⁻² produce a microbially safe juice. Both thermal and PL-treated juice samples were packed in ethylene vinyl alcohol pouches and stored at refrigerated conditions (4°C). The juice's microbial, enzymatic, and biochemical attributes were analyzed over 30 days of refrigerated storage. There is no significant influence (p < 0.05) on total soluble solids, pH, and titratable acidity. The thermally treated juice loses 36% of the total phenols and 22% of antioxidants. The loss of bioactive compounds is higher in thermal than in PL treatment. The shelf life of PL-treated juice is 25 days, and thermal treatment juice is 30 days, based on the microbial analysis (6 log₁₀ CFU mL⁻¹). The study affirms the potential of PL treatment as an alternative technique for preserving dragon fruit juice.