• UV-C decreased aerobic bacterial populations on the sweetpotato surface. • UV-C did not significantly reduce the incidence of sprouting. • UV-C did not affect external quality in sweetpotatoes (16-week storage) • % Weight loss in UV-C-treated sweetpotatoes gradually increased over storage time. UV-C light technology is rapidly being implemented for emerging applications in the fresh produce industry. The objective of this research is to evaluate the efficacy of 222 nm UV-C LEDs for inactivating aerobic bacterial cells on the surface of sweetpotato and potentially increase postharvest shelf-life. In this research, we exposed sweetpotatoes for a total of 18 weeks, a two-week curing period and a 16-week storage period, to two different UV-C doses: T1 (UV-C light intensity of 51.23 μW/cm 2 ), T2 (UV-C intensity of 153.68 μW/cm 2 ), and a control (no UV-C light treatment). The results showed that the high UV-C intensity of 153.68 μW/cm 2 significantly lowered the aerobic bacterial count (3.44 log CFU/100 g, survival population) compared to the control (4.05 log CFU/100 g) at 12 days after curing. Percent weight loss increased during storage for all treatments. A significant difference was recorded in week 16, as the T2 (153.68 μW/cm 2 ) treatment resulted in a 10.22% ± 0.24 weight loss, which was greater than the control (8.72% ± 0.59) and T1 (51.23 μW/cm 2 ) (8.78% ± 0.39) (p < 0.0001). Sprouting incidence did not differ significantly among treatments over the 16-week storage period. UV-C light treatments did not reduce the overall external quality of the sweetpotatoes throughout the 16-week period. UV-C light application during sweetpotato curing can lower microbial populations and does not impact external quality during storage. As growers continue to integrate food safety practices into production and storage systems, UV-C light may be an effective method to reduce postharvest spoilage of root crops.
Galipothu et al. (Wed,) studied this question.