Effects Of Pre-harvest ASA Treatments On Quality, Antioxidant Capacity And Volatile Compounds Of Muskmelon Fruit During Cool Storage

The muskmelons belong to climacteric fruit, and fruit easily breakdown quality and loss flavor during postharvest. Acetylsalicylic acid(ASA), as a derivative of salicylic acid, has the same physiological role with salicylic acid in plants. Asthe solubility of ASA is better than SA, it is easier for using. Muskmelons(cv. Jinhongbao) were emplyed as the materials, we study effect of spray ASA at 1.0 mmol/L during fruit development for four times, as young fruit period, fruit enlarging period, netting period and before 48 h of harvesting, on quality, antioxidant capacity and volatile compounds in fruits during cool temperature. The results indicated as follows:1. Pre-harvest ASA treatments significantly improved fruit firmness, TSS and decreased a, b of color at harvest. The difference of above mentioned paremeters intended closed between treatment and the control during storage. Pre-harvest ASA treatments had little effect on construction of cell wall at harvest; however, the treatment effectively maintained constructure of cell wall during storage. ASA treatments had no effect on weight loss, content of TA and L, h* of color at harvest and postharvest.2. Pre-harvest ASA treatments significantly increased antioxidant capacities of fruit at harvest and postharvest. The treatment had a higher antioxidant capacity of ABTS and DPPH than the control at harvest and postharvest. Although the treatment increased the content of H2O2 and of NOX activity at harvest, decreased them during the storage. Morever, the treatment had little effect on the content of Vcat harvest and postharvest.3. Pre-harvest ASA treatments promoted release of volatile substances, improved release of alcohols and aldehyde, and inhibited release ofestersat harvest. The differentce of content of volatile substances intended closed between treatment and the control during storage. Morever, the treatments alsoincreased the content of green note compounds of fruit, but decreased fruity note compounds.In conclusion, pre-harvest ASA treatments increase the firmness and content of TSS, delay yellowing, improve the total antioxidant capacity, and enhance release of volatile substances of fruits. It is suggested that ASA treatments affect muskmelon fruit quality, antioxidant capacities and release of volatile substances by inhabiting ethylene pruduction.