Effect of UV-C LEDs and heat treatments on microbial safety, chemical and sensory properties of sweet lime juice.

This study investigated the effect of 280 nm Ultraviolet-C light emission diodes (UV-C LEDs) on the microbial safety and quality attributes of sweet lime juice (SLJ), focusing on E. coli and L. monocytogenes. SLJ samples were irradiated with dosages of 0, 252.96, 505.92, and 758.88 mJ/cm2. At 758.88 mJ/cm2, significant microbial reduction up to 5.45 and 6 log10 CFU/mL for E. coli and L. monocytogenes were achieved, respectively. Physicochemical properties, colour, browning index, aroma, and flavour profile were assessed. Results showed no significant changes in pH and titratable acidity, except in heattreated samples. Colour and browning index were affected in heat and UV-C LEDs treated samples. E-Nose and E-Tongue analysis indicated minimal changes in aroma and significant changes in taste profiles. Nineteen compounds were identified and quantified using 1H NMR spectroscopy. UV-C LEDs reduced microbial contamination without modifying physicochemical and sensory properties, offering a viable alternative to traditional heat treatments.