UV-C Treatment Maintains the Sensory Quality, Antioxidant Activity and Flavor of Pepino Fruit during Postharvest Storage

This study examines ultraviolet-C (UV-C) treatment supplementation as a means of inhibiting the senescence of pepino fruit after harvest. Pepino fruits were subjected to 1.5 kJ/m2 UV-C treatments and then packed and stored at 10 °C for 28 d. Results showed that 1.5 kJ/m2 UV-C treatment had the greatest ability to maintain firmness, and reduced the level of respiration and ethylene production. Further analysis indicated that the 1.5 kJ/m2 UV-C treatment maintained the content of total soluble solids (TSS), chlorophyll, vitamin C, flavonoids, and total phenolics. Lower levels of malondialdehyde (MDA) and higher levels of antioxidant enzyme activity were found in UV-C treated fruit during storage. An electronic nose (E-nose) and headspace-gas chromatography-mass spectrometry (HS-GC-MS) was used to determine volatile compounds. Results revealed that the UV-C treatment may promote the synthesis of a large number of alcohols and esters by maintaining the overall level of acids, aldehydes, and esters in fruits. This may contribute to the maintenance of the flavor of harvested fruits. In conclusion, 1.5 kJ/m2 UV-C treatment was demonstrated to be an effective treatment for the maintenance of the sensory, nutritional, and flavor parameters of pepino fruit.