Analysis of Aroma Differences between Yingjiang Camellia taliensis and Fengqing Large-leaved Species Bud Tea

In this study, sensory evaluation and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to identify and analyze the volatile components of Yingjiang Camellia taliensis bud tea (usually called spore tea, marked as spore black tea YBH, spore white tea YBB) and Fengqing large-leaved species bud tea (marked as Fengqing black tea FQH, Fengqing white tea FQB) in order to investigate the aroma composition and differences between Yunnan Yingjiang Camellia taliensis bud tea and Fengqing large-leaved species bud tea. The results of HS-SPME-GC-MS showed that a total of 616 volatile metabolites from 16 categories were detected in the four tea samples. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) showed that in the comparison of two varieties of black tea, 8 unique differential metabolites were detected in YBH, and 7 unique differential metabolites in FQH, while in the comparison of two varieties of white tea, 3 unique differential metabolites were detected in YBB and 4 unique differential metabolites in FQB. The odor activity value (OAV) evaluation of the main characteristic differential volatile metabolites showed that (Z)-2-decenal and geraniol were the potential characteristic aromas to distinguish Yingjiang Camellia taliensis and Fengqing large-leaved species, (Z)-2-decenal (OAV>100) was an important aroma component of Yingjiang Camellia taliensis. It was speculated that damascenone (OAV>1) was the key substances for YBH to produce strong flower and fruit aroma. Caproic acid and linalyl acetate might be the main substances of YBB with natural flower fragrance. β-Ionone (OAV>10) was an important aroma component of Fengqing large-leaved species. It was speculated that benzaldehyde (OAV>1) was the main substance of FQH with flower aroma, and (Z)-2-decenal and caproic acid were the main substances of FQB with floral and fragrance. In summary, the aroma components of Yingjiang Camellia taliensis spore tea are richer than the control variety and the aroma of YBH is more fragrant.