The Influence Of Postharvest BTH Treatment On LOX Activity And CharacteristicAroma Of ’Yujinxiang’ Melon

“Yu jinxiang” melon is important economic crop in China.The quality of fruits aredeterioration for rot easly,because its’ harvest is at hot summer.Postharvest BTH treatment ofinduced resistance can effectively improve its’ disease resistance,reduce fruit postharvestdecay.The fruits of “Yu jinxiang” melon was material,they were soaked with BTH solutionafter harvest.During storge at ambient temperature,the activity change of LOX enzyme wereanalized in pulp and peel.And the aroma components were determined and quantified bySPME with GC-MS,GC technology.The effects of BTH induced resistance were studied onfruit aroma and LOX enzyme activity.The results showed that:1.The LOX enzyme activity of postharvest BTH induced samples were higher thancontrol samples during storage.The LOX activity of peel tissue was slightly higher than thepulp tissue.Postharvest BTH treatment would enhanced LOX activity of “Yu jinxiang”melon.2.During storage,45aroma compounds were identified in the pulp tissue,including19esters,9alcohols,8aldehydes,2ketone,6alkanes,1acid,the relative content were64.14%,28.12%,6.86%,0.13%,0.72%,0.13%;45aroma compounds were identified in the peeltissue,including19esters,9alcohols,8aldehydes,2ketone,6alkanes,1acid,the relative contentwere71.37%,18.02%,9.18%,0.25%,1.10%,0.08%.The esters was most in “Yu jinxiang”melon.3.The postharvest BTH treatment would inhibit release of esters,alcohols,aldehydes,alkanes from pulp and peel tissue,and increase release of ketone.The relative release amountof esters, alcohols,aldehydes,alkanes were77.88%,86.65%,89.62%,86.65%in pulp tissue ofthe control sample.The relative release amount of esters,aldehydes,alkanes were97.17%,62.07%,96.07%in skin tissue of the control sample.Ketones’ release quantity of BTHtreatment sample were1.49and1.17times in pulp and peel tissue of the control sample.4.The postharvest BTH treatment would increase release of (Z)-3-hexen-1-ol,hexanal,(Z)-6-nonenal,nonyl acetate from pulp and peel tissue,and inhibit release of trans,cis-2,6-nonadienal,(2E,6Z)-2,6-nonadien-1-ol,ethyl acetate.The effects of BTH treatment inpeel tissue was slightly higher than the pulp tissue.The release of (Z)-3-hexen-1-ol,hexanalwere1.77and1.97times in pulp tissue of the control sample.The release of (Z)-3-hexen-1-ol,hexanal,(Z)-6-nonenal,nonyl acetate were9.85,1.73,1.77and1.37times of the controlsample. 5.The fruit flavor and melon aroma substance were inhibited by postharvest BTHtreatment,which were ethyl acetate,butanoic acid methyl ester, cis-2,6-nonadienal,(2E,6Z)-2,6-nonadien-1-ol.The green and grass scent aroma substances were enhanced by postharvestBTH treatment,which were (z)-3-Hexen-1-ol acetate,(Z)-3-hexen-1-ol.