Title: UV-C IRRADIATION PREVENTS BREAKDOWN AND CHILLING INJURY OF PEACHES DURING COLD STORAGE
Gonzalez-Aguilar, G - CIAD, MEXICO
Buta, Joseph - ARS, RETIRED
Submitted to: Journal of the Science of Food and Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 4, 2003
Publication Date: December 1, 2004
Citation: Gonzalez-Aguilar, G., Wang, C.Y., Buta, J.G. 2004. Uv-c irradiation prevents breakdown and chilling injury of peaches during cold storage. Journal of the Science of Food and Agriculture. 84:415-422
Interpretive Summary: Decay of fruits and vegetables is one of the major causes of postharvest losses in fresh produce. Various methods have been used to inhibit decay. Most of these methods involve the use of fungicides. Increased resistance of many pathogens to fungicides and recent health concerns over pesticide contamination of food have resulted in the withdrawal of a number of key fungicides from the market. These developments have stimulated the search for alternative methods of treatment. We have found that by using brief periods of UV-C irradiation, we can maintain better quality of peaches as compared to the unirradiated control fruit. After 3, 5 or 10 minutes of exposure of peaches to germicidal (UV-C) lamps, fungal decay and chilling injury of the fruit were reduced during and after storage at 5 degree C. No UV-damage was observed on treated fruit after storage. Information presented in this study is of interest to other postharvest researchers and is useful to the produce industry.
Prestorage exposure of peaches (Prunus persica cv. "Jefferson") with UV-C irradiation for 3, 5 or 10 min significantly reduced chilling injury after 14 and 21 days of storage at 5 degree C plus 7 days of shelf-life at 20 degree C. Similar reduction in fungal decay was also found by these treatments. Skin browning and UV damage were found to be moderate to severe in peaches after the 15 or 20 min UV-C treatment. The 20 min exposure accelerated deterioration. Fruit treated with UV-C for 3, 5, or 10 min remained firmer and softened more slowly than the control and those treated with longer durations of exposure. No differences were found in weight loss or respiration rates among all the treatments. However, ethylene production was stimulated by all of the UV-C treatments compared to that of the control. Putrescine levels increased initially after 3 or 5 min exposure to UV-C. A tendency toward higher accumulation of spermidine and spermine was found in peaches after UV exposure. These higher levels of polyamines apparently are a response to the UV-C irradiation and might be beneficial in increasing the resistance of fruit tissue to deterioration and chilling injury.