Effect of Scenting on Aroma of Different Types of Dark Tea

In this study, solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography-quadrupole time-of-flight mass spectrometry (GC × GC-Q-TOF-MS) were used for the qualitative and quantitative determination of volatile components in dark tea samples, and the characteristic volatile components of jasmine dark tea were identified by multivariate statistical analysis and their regulatory effects on tea aroma were investigated. The results showed that the scenting process could coordinate the aroma characteristics of dark tea (such as aged, woody and smoky pine aroma), and endow dark tea with the aroma of jasmine, contributing to the aroma quality of jasmine dark tea that is defined as “fresh flowery fragrance, and pure tea-like fragrance”. A total of 366 volatile components were identified in dark tea and jasmine dark tea, of which 38 volatile components such as linalool, α-farnesene, and benzyl acetate were characteristic volatile components to distinguish the aroma quality of dark tea before and after scenting, and most characteristic volatile components were positively correlated with jasmine and fungus fragrance, and negatively correlated with aged woody and smoky pine aroma. These findings led us to conclude that scenting is important for improving the quality of jasmine dark tea. This study provides a theoretical basis for improving the processing technology and quality and regulating the aroma of jasmine dark tea.