Ultraviolet irradiation as alternative non-thermal cold pasteurization to improve quality and microbiological...

The objectives of this research were to study the effect of UV irradiation on quality characteristics of mango juice during cold storage. Mango juice exposed to UV radiation was also used to determine zero-order and first-order kinetic models of microbial (total plate count, yeast and mold count, and Escherichia coli) reduction. According to the microbiological results, UV light at 120 J/cm² caused a 5.19 log reduction. It was found that microbial inactivation of all tested microorganisms followed first-order kinetic model. The treatments did not differ significantly in terms of the quality metrics. L*, b*, pH, total soluble solid, total phenolic compound, total flavonoid content, and antioxidant activity as measured by the DPPH and FRAP assay all tended to decline during storage at 4 °C, whereas a*, ∆E, titratable acidity, total plate count, yeast and mold count, as well as the total plate count, had an increasing trend. During storage at 4 °C, UV irradiation increased the shelf life of mango juice by about 14 days compared to the control sample. In conclusion, this study demonstrated the potential of UV treatment as an alternative to thermal pasteurization for preserving mango juice quality and safety while also prolonging shelf life.