Characterization of the volatile compounds profile of the innovative broken oolong-black tea in comparison with broken oolong and broken black tea

Abstract

Broken oolong-black tea is an innovative tea in China produced by applying characteristic manufacture crafts of broken oolong tea (bruising) and broken black tea (fermentation) on the manufacture of tea and it has both aroma features of broken oolong tea and broken black tea. The aim of this study is to investigate the differences of the volatile compounds among broken oolong-black, broken oolong and broken black tea made by Huangzhixiang (HZX) and Huangdan (HD) varieties by gas chromatography-mass spectrometry (GC-MS) combined with chemometirc analysis. The results suggested significant differences on both aroma quality and volatile compounds profile of three kinds of tea. Chemometric analysis showed that 47 and 52 differential volatile compounds were identified to distinguish three kinds of teas made by HZX and HD, respectively, and the differences of volatile compounds among the tea samples were mostly quantitatively rather than qualitatively. Besides, compounds with floral and fruity aroma increased in broken oolong-black tea compared with the others, while compounds with green aroma decreased in broken oolong-black tea. Quantitative descriptive analysis of the aroma showed that sweet aroma was a new trait of broken oolong-black tea compared with broken oolong tea while green aroma disappeared compared with broken black tea. Our results provide the theoretical and practical meaning for the application of two characteristic crafts from different tea manufacture on the innovation of tea manufacture.