Postharvest UV-C treatment reduces postharvest decay in sweet cherries stored at ambient temperature (20°C)

Postharvest treatment with UV-C (180-280 nm) has been shown to significantly extend the shelf-life of many horticulture crops. In this study, two sweet cherry cultivars (‘Sweetheart’ and ‘Lapin’) were exposed to UV-C light at five different intensities (0, 2.1, 9.7, 25.3, 50.8 kJ m^-2) and stored for up to 9 days at 20°C or 28 days at 1°C. Fruit quality was assessed by stem colour, stem attachment, development of postharvest rots, flesh colour, fruit firmness, total soluble content and titratable acidity. Fruit exposed to UV-C treatment and storage at 20°C experienced significantly lower levels of postharvest rot, but this response to UVC treatment was not dose dependent. In contrast, UV-C treatment was found to have no significant effect on decay development for treated fruit when later stored for up to 28 days at 1°C. UV-C treatment exhibited no significant impact on stem colour, flesh colour, stem detachment, TSS, TA nor TSS/TA ratio for fruit stored at 20°C, although treated ‘Lapin’ fruits, showed significantly greater firmness retention relative to the control. Results indicated that under certain conditions, postharvest UV-C treatment has the potential to reduce the incidence of decay and maintaining flesh firmness in sweet cherries stored at ambient temperature (20°C), however, there was no significant effect when stored at 1°C.