Discriminant Analysis of Aroma Types of Flue-cured Tobacco on Neutral Aroma Components

In order to distinguish characteristics of aroma types of flue-cured tobacco and establish mathematical model for judgment of aroma types.Contents of neutral aroma components in flue-cured tobacco of different aroma types were analyszed which were based on 61 samples(C3F) from 11 main tobacco production provinces of China.Stepwise discriminant analysis was applied to different aroma types tobacco leaves using 24 neutral aroma components and discriminant function was expressed.The results showed that contents of neutral aroma components in middle aroma type were the highest [(467.562±96.188) μg/g],following as full aroma type [(417.115±113.166) μg/g],and then clean aroma type [(377.267±56.677) μg/g].The contents of 13 components in middle aroma type were the highest,the 8 components in full aroma type and 2 components in clean aroma type.The results of discriminant analysis indicated that 10 neutral aroma components(β-damascenone,6-methyl-5-heptene-2-dione,hexanal,3-oxo-α-ionol,benzyl alcohol,pyrrole,phenylacetaldehyde,linalool,neophytadiene,megastigmatrienone) were used in the discriminant function and found discriminant model.Self-validation method and Cross-validation method were applied to back evaluation on original sample.The accuracy of back evaluation were 93.44% and 88.52% respectively.The other 22 samples were predicted using this modle,the accuracy of predicted samples about 3 kinds aroma types(full aroma type,middle aroma type,clean aroma type) were 88.89%,100%,85.71% respectively.In conclusion,the discrimination method had its own advantage and could be used to identify aroma type of flue-cured tobacco accurately and quickly.