APPLICATION OF NITRIC OXIDE TO EXTEND THE SHELF LIFE OF MANGO FRUIT

Abstract

Nitric oxide (NO), a highly reactive free radical gas, has been used as a postharvest treatment to delay fruit ripening and senescence. NO inhibits ethylene production and extends the shelf life of various fruit. The objective of this research was to determine the effect of sodium nitroprusside (SNP), a NO donor, on the quality of mango fruit during storage. Uniform and unblemished mango fruit cv. Nam Dok Mai Si Thong were soaked in 0.5 or 1 mM of SNP for 10 min; dipping in water for 10 min served as the control. After treatment, all fruit were stored at ambient temperature (22°C). Both SNP concentrations significantly reduced ethylene production and respiration rate. Only 1 mM SNP maintained firmness and delayed the changes in soluble solid content and titratable acidity. SNP also delayed color development of the pulp, with fruit treated with 1 mM SNP showing the highest L* and hue angle values and lowest a* and b* values. However, SNP had no effect on weight loss compared to the control. The results indicate that SNP treatment at 1 mM for 10 min can be used to maintain quality and extend shelf life of ‘Nam Dok Mai Si Thong’ mango fruit.