UV-C light preserves quality of minimally processed watermelon cylinders
Watermelon (Citrullus lanatus) is usually minimally processed as cubes, edge-cut damage being a remarkable defect. To avoid such disorder, processing as cylinders and using UV-C as sanitizing tool can be an interesting alternative to preserve quality during shelf life. The effect of UV-C radiation on overall quality, microbial growth, phenolics content and lycopene concentration of watermelon cylinders (2.7 cm ɸ) of several lengths (1, 2, 4 and 8 cm) were analyzed. After harvesting, fruits were washed (150 µL L-1 NaClO), precooled and processed at 8°C. Once removed the skin, fruits were manually cut as cylinders, exposed to 4.79 kJ UV-C m-2 and packaged in polypropylene packages under passive modified atmosphere. UV-C untreated cylinders were used as control. After 7 days at 5°C, O2 partial pressure was higher for the longest cylinders (17.9 kPa for 8 cm vs. 14.2 kPa for 1 cm) with the lowest CO2 partial pressure (3 kPa for 8 cm vs. 7.4 kPa for 1 cm), indicating a higher respiration rate for the smaller sizes. A better sensory quality in 8 cm cylinders for both, control and UV-C treated, was observed. However, microbial growth was better controlled and phenolics content better maintained (60-80 mg CAE kg-1 fw) in UV-C treated samples. Lycopene content did not significantly decrease in any treatment. As conclusion, watermelon minimally processed as cylinders pretreated with 4.79 kJ UV-C m-2 can be stored for up to 7 days at 5°C without noticeable quality changes.
Gómez, P.A., Robles, P.A., Tomás-Callejas, A., Otón, M., Artés, F. and Artés-Hernández, F. (2017). UV-C light preserves quality of minimally processed watermelon cylinders. Acta Hortic. 1151, 279-286
Citrullus lanatus, fresh-cut, postharvest, lycopene, phenolics