Mass Fraction of Sugar and Acid and Flavor Index of Pear Cultivars(Pyurs bretschneideri) at Different Ripening Stages

Sugar and acid components and its content in nine defferent ealy,middle and late ripening pear cultivars was studied by testing components of fruit sugar and organic acid,and then,the flavor index of the different cultivars was calculated and compared.The result showed that different ripening pear cultivers had much different sugar,acid mass fraction and components,under the condition of little difference in total sugar or acid mass fraction among the different cultivars,the mass fraction of glucose,fructose and sucrose,and citric acid,malic acid and succinic acid of the different cultivars were significantly different,so the fruit flavor index could more reflect the ‘real'flavor of the pear fruits than the ratio of sugar acid.Considering the flavor index,the optimal cultivars for early-ripening,mid-ripening and late-ripening were‘Xueqing',‘Huangguan'and‘Xuehua'.