Discriminant analysis of aroma types of upper leaf in flue-cured tobacco based on chemical constituents and aroma components

In order to distinguish characteristics styles of aroma types of flue-cured tobacco upper leaves and establish mathematical model for judgment of aroma types,contents of chemical constituents and aroma components in flue-cured tobacco were analyzed which were based on 65 samples(B2F) from 11 main tobacco production provinces of China.Stepwise discriminant analysis was applied to discriminate tobacco leaves based on 67 chemical constituents and aroma components and the discriminant function was established.The results showed that total contents of aroma components in middle aroma type were the highest,followed by clean aroma type and then the full aroma type.There was little difference among the highest contents of aroma components in the three aroma types.And contents of total sugar and reducing sugar in clean aroma type were very significantly higher than those in the other two aroma types.Difference of chemical constituents and aroma components exited in certain dominated aroma type.Besides,there were diversity and difference in the aroma type of flue-cured tobacco of the same region.The results of discriminant analysis indicated that 12 neutral aroma components(total sugar,reducing sugar,3-methyl-1-butanol,2-pyridinecarboxaldehyde,2,4-heptadienal,2-ethylpyridine,nonanal,phenethyl alcohol,benzo[c]thien,menthone,butylated hydroxytoluene,3-oxo-α-ionol) were used in the discriminant function and found discriminant model.Self-validation method and Cross-validation method were applied to reevaluate the original sample.The accuracy of reevaluation was 100% and 98.33%,respectively.The other 19 samples were predicted by this model,the accuracy of predicted samples for the 3 kinds of aroma types(clean aroma type,middle aroma type,full aroma type) were100%,100%,83.33%,respectively.