Influence of Drying Method on Volatile Flavor Substances of Raw Dark Tea Investigated by HS-GC-IMS

Abstract:

Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to analyze the volatile flavor substances of dried raw dark tea treated with bake drying and sun drying. The results showed that 65 volatile substances were identified in the two drying methods, including 23 aldehydes, 13 esters, 11 alcohols, 10 ketones, 3 heteroxides, 2 hydrocarbons, 2 pyrazines and 1 acid. The HS-GC-IMS fingerprint spectrum visually displayed the differences of volatile flavor between the bake-dried and sun-dried raw dark tea samples. Similarity and principal component analysis showed that each group of samples had their own specific volatile flavor substances, and sun-dried raw dark tea would release more characteristic volatile substances. The similarity between the two drying methods was low, and the raw dark tea dried by different methods were significantly distinguished. This study could provide a theoretical basis for the processing and flavor quality control of raw dark tea.