Abstract

In this study, we measured 8 kinds of typical Yunnan Pu'er tea utilizing Electronic Nose technology. The analyses are achieved by the software Winmuster and the analyzing methods include Principal Component Analysis (PCA), Linear Diseriminant Analysis (LDA) and loading. The PCA shows that the different aroma of Pu’er tea caused by different processing technic (fermented and unfermented) can be totally (100%) differentiated. The LDA shows that by choosing appropriate discriminant, we can discriminate two kinds of Pu’er tea that are manufactured by the same manufacturer in the same year but proceed by different technic. This illustrates that distinct discrepancy of components of volatiles exist in Pu’er tea proceed by different technic, which can be identified by Electronic Nose. The result of Loading indicates that out of 10 sensors, 3 key sensors labeled as 2, 7, 9 have responded acutely to tea aroma, which have contributed most to the identification. The overall result presents that this new quick and nondestructive technique-Electronic Nose is a effective way to evaluate the quality of tea through aroma, which can be used to the detection of aroma content of Yunnan Pu’er tea because of its excellent discrimination of fermented and unfermented tea.

Keywords:

Aroma, electronic nose, Yunnan Pu,

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Competing interests

The authors have no competing interests.

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