Effect of different storage conditions on the quality attributes of sweet lime juice subjected to pulsed light and thermal pasteurization

Abstract

The primary issue of the sweet lime juice processing industry is its limited stability. The aim of this study is to examine the shelf life of pulsed light (PL) treated sweet lime juice at 4, 15, and 25 °C while packed in two different packaging materials (coextruded ethylene vinyl alcohol copolymer [EVOH] and multi-layered polyethylene terephthalate [ML PET] films). The PL-treated (3000 J cm⁻²) juice was analyzed for microbial count, enzyme activity, bioactive compound degradation, and sensory attributes for up to 46 days. Different packaging materials and storage temperatures had a significant effect (p < 0.05) on the microbial, enzyme inactivation, and biochemical attributes but had no significant influence (p > 0.05) on pH, acidity, and soluble solids in the samples. The juice treated under equivalent thermal conditions (95 °C/5 min) and PL-treated juice possessed sensory scores of 5.8 and 7.2, respectively. The PL-treated juice preserved 23% more antioxidants, 12.6% more phenolics, and 35.3% more vitamin C than the thermally pasteurized beverage after 46 days of storage (at 4 °C). The juice stored in ML-PET had a better shelf life and nutrient retention than that in the EVOH pouch. Interestingly, the sensory score and vitamin C profile were above the allowable limit even after 46 days of storage at 4 °C. However, the microbial count (>6 log cfu mL⁻¹) restricted the shelf life up to 46, 30, and 13 days, at 4, 15, and 25 °C, respectively for the juice packed in the ML-PET pouch. To conclude, PL can be a great non-thermal technology to extend the shelf life of sweet lime juice from 6 to 46 days during refrigerated storage (4 °C).