|Hodges, D. Mark - AGRI-FOOD CANADA|
Submitted to: Postharvest Biology and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 27, 2007
Publication Date: March 31, 2008
Citation: Lester, G.E., Hodges, D. 2008. Antioxidants associated with fruit senescence and human health: Novel orange-fleshed non-netted honey dew melon genotype comparisons following different seasonal productions and cold storage durations. Postharvest Biology and Technology. 48(3):347-354. Interpretive Summary: This study demonstrates there are germplasm (cultivar) differences in heightened postharvest shelf-life, vitamins (C, beta-carotene, folic acid), minerals (calcium iron, magnesium, potassium), and antioxidants between non-netted, orange-fleshed honey dew melon fruit. Our findings corroborate previous publications that non-netted, orange-fleshed honey dew melon is an excellent fruit option with both a long marketable shelf-life and high human health-bioactive nutrient content. Moreover, the lack of a netted rind and the associated food-safety issues with netted cantaloupe makes this melon type a safer food choice. As non-netted, orange-fleshed honey dew melon germplasm is a relatively new fruit type to many melon producers, additional in-field evaluations are required to characterize/ maximize consumer health and postharvest attributes.
Technical Abstract: Consumption of netted, orange-fleshed cantaloupe melons (Cucumis melo L. Reticulatus group) continues to raise food-safety concerns due to attachment of enteric bacteria to sites on the netted surface inaccessible to sanitation. Non-netted, orange-fleshed honey dew melons (Cucumis melo L. Inodorus group) vs. cantaloupe offers to be a safer and a healthier (nutritional content) option. The purpose of this study was to compare some commercially available non-netted, orange-fleshed honey dew melon cultivars and a breeding line fruit for levels of antioxidants associated with both storage quality and human health. Fruit were produced in both autumn and spring production cycles in a glasshouse, harvested at abscission (mature) and stored for up to 24 d at either 5 degrees C or 10 degrees C. Spring versus autumn production generally yielded higher overall levels of folic acid, calcium, malondialdehyde (MDA), and lipophilic total antioxidant capacities. ‘Orange Delight’ and ‘Orange Dew’, generally were superior to ‘Honey Gold’, ‘Temptation’ and a breeding line as they consistently demonstrated some of the highest levels of total ascorbic acid, beta-carotene, and potassium. ‘Orange Delight’ and ‘Orange Dew’ were also among the cultivars with the highest activities of ascorbate peroxidase, catalase and superoxide dismutase. ‘Orange Delight’ and ‘Orange Dew’ also exhibited the least increase in MDA (i.e., lipid peroxidation) during storage suggesting that antioxidant levels in these two cultivars limited oxidative-related senescence/postharvest quality decline compared to the other three genotypes. Our results indicate that there are significant differences in human-health- and storage quality-related phytochemical profiles between orange-fleshed honey dew melon cultivars, and that high antioxidant levels are associated with reduced lipid peroxidation during melon fruit storage.