Postharvest UV-C Irradiation Delays Senescence and Maintains Nutritional Properties of Broccoli Florets

Health promoting bioactive compounds in broccoli (Brassica oleracea L. var. italica) florets decrease in nutritional value after harvest. Ultraviolet (UV)-C radiation (254 nm) is a physical technology to extend postharvest life of vegetables. Broccoli florets from cv. Premium Crop, were treated with 0 m−2·s−1 (control), 1.5, 4.5, or 10 kJ·m−2·s−1 of UV-C and subsequently stored at 4°C for 12 days. All treatments increased total polyphenols content and increased up to 21% above the initial value during storage. The higher the UV-C dose, the higher the total antioxidant capacity values that were reached. Generally total chlorophyll content decreased, but higher chlorophyll retention was when broccoli florets were radiated with 4.5 and 10 kJ·m−2·s−1 of UV-C. Treatment with UV-C of 10 kJ·m−2·s−1 caused the highest retention of sugar. Decreasing protein content in broccoli florets during storage occurred but samples treated with 4.5 and 10 kJ·m−2·s−1 had higher protein contents. UV-C treatment is a nonchemical technique to delay senescence and preserve quality and nutritional value of broccoli up to 12 days at 4°C.