Lushan Yunwu tea (LSYWT) is a famous green tea in China. However, the effects of intercropping tea with flowering cherry on the overall aroma of tea have not been well understood. In this study, headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used for analysis. A total of 54 volatile compounds from eight chemical classes were identified in tea samples from both the intercropping and pure-tea-plantation groups. Principal component analysis (PCA), orthogonal partial least-squares discriminant analysis (OPLS-DA), and odor activity value (OAV) methods combined with sensory evaluation identified cis-jasmone, nonanal, and linalool as the key aroma compounds in the intercropping group. Benzaldehyde, α-farnesene, and methyl benzene were identified as the main volatile compounds in the flowering cherry using headspace solid-phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS). These findings will enrich the research on tea aroma chemistry and offer new insights into the product development and quality improvement of LSYWT.
The treatment of black tea fermentation with different exogenous tannases was investigated, and processing parameters during black tea fermentation, including fermentation time, fermentation temperature, and exoenzyme amounts, were optimized, while the consumption and transformation pathways of catechins were analyzed. The results showed that tannase from Aspergillus niger was ultimately selected as the optimal enzyme to effectively increase the content of theaflavins by promoting the hydrolysis reaction and benzoylation reaction of catechins, resulting in a greater theaflavin (TF) content of 1.41%. The optimal processing conditions were found to be a fermentation time of 3 h, a fermentation temperature of 20 °C, and 1 g of tannase for 300 g of rolled tea leaves. Processing with the exogenous tannase could provide an ideal choice for the efficient utilization of summer and autumn fresh tea leaves, and could be used to develop summer and autumn black tea and to improve the content of theaflavins. It could also be used to develop deep processing of tea products with theaflavin extracts in the future.