Headspace Solid Phase Microextraction Combined with Gas Chromatography-Mass Spectrometry Analysis of Aroma Characteristics of White Tea from New Strain ‘Baiyun 0492’

Abstract

The aroma components of white tea from the new tea strain ‘Baiyun 0492’ (also known as Baiyun Tezaocha) and ‘Fuyun 6’ as a control were analyzed and compared by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) in an effort to identify the characteristic aroma components of ‘Baiyun 0492’ white tea. A total of 928 aroma compounds were detected in six white tea samples (of three different grades for each type), and nonyl acetate, contributing to floral and fruity aromas, might be an aroma compound unique to ‘Baiyun 0492’ tea. The results of relative odor activity value (ROAV) analysis showed that β-ionone, linalyl acetate, linalool, (Z)-decan-2-enal, damascenone, neral and citral were the key aroma components in both white teas. Based on orthogonal partial least squares-discriminant analysis (OPLS-DA), the contents of linalool, methyl benzoate, hotrienol, nonyl acetate, 3,7-dimethy-6-actenoic acid and geranyl formate in ‘Baiyun 0492’ tea were significantly higher than those in ‘Fuyun 6’ tea (variable important in the projection (VIP) >1, P < 0.05). Linalsol and methyl benzoate were important aroma compounds of ‘Baiyun 0492’ white tea, responsible for pekoe-like, fruity and floral aromas. This study is helpful for a comprehensive understanding of the aroma characteristics of ‘Baiyun 0492’ white tea, and provides a scientific basis for the research and development of ‘Baiyun 0492’ white tea products with distinctive personality.

Keywords

• white tea; ‘baiyun 0492’; aroma; grade