ARS | Publication request: COMPARISONS BETWEEN ORANGE- AND GREEN-FLESHED NON-NETTED AND ORANGE- FLESHED NETTED MUSKMELONS: ANTIOXIDANT CHANGES FOLLOWING DIFFERENT HARVEST AND STORAGE PERIODS

Submitted to: Journal of the American Society for Horticultural Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 10, 2005
Publication Date: January 25, 2006
Citation: Hodges, D., Lester, G.E. 2006. Comparisons between orange- and green-fleshed non-netted and orange-fleshed netted muskmelons: antioxidant changes following different harvest and storage periods. Journal of the American Society for Horticulture Science. 131:110-117.

Interpretive Summary: Due to the lack of a netted rind, non-netted orange-fleshed honey dew (‘Orange Dew’) does not represent the risk to consumers as does netted muskmelon (‘Cruiser’), as human illness pathogens can remain present in the inaccessible netting. Furthermore, both orange- (‘Orange Dew’) and green-fleshed (‘Honey Brew’) non-netted cultivars evinced less lipid peroxidation, and hence postharvest senescence, during the 17 d storage period then the netted muskmelon ‘Cruiser’. Higher AsPX and SOD activities in ‘Orange Dew’ and ‘Honey Brew’ appear to confer a greater resistance to lipid peroxidation in these muskmelon genotypes than to the netted ‘Cruiser’. ‘Orange Dew’ appears to be a healthier food choice, not only due to its lack a netted rind which could potentially harbour human illness-related pathogens, but also that it was superior to both ‘Cruiser’ and ‘Honey Brew’ in overall beta-carotene and phenolic levels.

Technical Abstract: The consumption of netted muskmelons (Cucumis melo L. Reticulatus group) has raised health concerns due to Salmonella and other bacteria attaching to inaccessible sites on the netted rind. The purpose of this study was to compare 1) the enzymic and non-enzymic antioxidant capacity between representative cultivars of netted muskmelon and both green- and orange-fleshed honey dew muskmelons during storage for 17 days and 2) levels of non-nutrient phytochemicals between these genotypes in consideration of ultimately substituting netted orange-fleshed with non-netted orange-fleshed muskmelon. Netted muskmelon (‘Cruiser’), green-fleshed (‘Honey Brew’), and orange-fleshed (‘Orange Dew’) muskmelons were harvested in Texas at the beginning (May 21) and at the end (June 11) of the production season in 2004. Storage treatments were zero days, or stored following simulated commercial storage plus retail display temperatures for 7 days at 7°C and 95% + 2% RH plus 3 days at 21°C, or 14 days at 7°C and 95% + 2% RH plus 3 days at 21°C. Both ‘Orange Dew’ and ‘Honey Brew’ non-netted cultivars evinced similar and less lipid peroxidation, and hence postharvest senescence, during the 17 d storage period then the netted muskmelon ‘Cruiser’. In comparison with ‘Cruiser’, ‘Orange Dew’ generally demonstrated higher concentrations of ß-carotene and phenolics and, with few exceptions, higher activities of the antioxidant enzymes ascorbate peroxidase (AsPX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT), guaiacol peroxidase (POX), and superoxide dismutase (SOD). Higher AsPX and SOD activities in both ‘Orange Dew’ and ‘Honey Brew’ appear to confer a greater resistance to lipid peroxidation in these muskmelon genotypes than to the netted ‘Cruiser’. ‘Orange Dew’ also appears to be a healthier food choice not only due to its lack of a netted rind which could potentially harbour human illness-related pathogens such as Salmonella, but also that it was superior to both ‘Cruiser’ and ‘Honey Brew’ in overall beta-carotene and phenolic levels.