Extraction of Volatile Compounds and Analysis of Aroma Characteristics in Fenggang Zinc-Selenium Tea

In order to explore the variation of volatile components of Fenggang zinc-selenium tea during the production process. The combination of headspace solid phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) was applied to detecte volatile components of Fenggang zinc-selenium tea during the production process, and optimize the extracting conditions. Principal component analysis and orthogonal partial least squares discriminant analysis were used to determine, distinguish and screen the volatile components of Fenggang zinc-selenium tea during the production process. The results showed that the best extraction process was as follows: Ratio of raw material to water was 1:6 (g/mL), extraction fiber 50/30 μm CAR/DVB/PDMS, extraction temperature at 90 ℃, extraction time for 70 min. A total of 91 volatile substances were identified by GC-MS that there were 37 kinds of common characteristic volatile components in the Fenggang zinc-selenium tea during the production process. Alcohols, ketones, esters and aldehydes were the main volatile components constituting the aroma of Fenggang zinc-selenium tea, among which alcohols were the most abundant and the highest content. Fenggang zinc-selenium tea could be divided into one category before processing and one category after processing by principal component analysis, and orthogonal partial least squares discriminant analysis showed that 15 volatile components contributed significantly to the odor of Fenggang zinc-selenium tea. Jasmonone, (S)-oxidized linalool, α-ionone, methyl salicylate, methyl heptenone, (E)-oxidized linalool, cedarol, β-cyclic citral, 2-pyrrol 6-trimethyl-6-vinyl tetrahydro-2H-furan-3-ol and methyl acetylsalicylate played an important role in the characteristic aroma quality of Fenggang zinc-selenium tea. This study can provide a theoretical basis for the production, processing, quality control of Fenggang zinc-selenium tea.