Abstract: GC-MS was employed to detect the volatile compounds in six categories of teas processed from fresh leaves of the single tea cultivar,Camellia sinensis var. Meizhan in this study. Moreover, to compare the differences among the six teas on the aroma formation, the characteristic components and key variables of teas were screened by statistical analysis, and the contribution of each volatile compound to the aroma was evaluated by calculating the odor activity value (OAV) and aroma character impact value (ACI). The results showed that in addition to the characteristic components of each tea, a total of 10 compounds, including ocimene, (E)-nerolidol, β-caryophyllene, etc., were screened out, and the changes of their content play a major role in the formation of differential tea aroma. Moreover, green tea and white tea possessed high proportions of compounds with fragrant properties in their aroma composition. Yellow tea had a relatively balanced proportion of green, floral, and fruity aroma compounds. Oolong tea had a high proportion of floral aroma compounds. Further study revealed that floral and fruity aroma compounds were dominant in black tea, and the proportion of fruity aroma compounds in dark tea was significantly higher than in other teas. Besides, different processing methods could regulate the aroma formation of the six categories of teas by influencing the composition and content of volatile compounds. We have also confirmed the important contribution of the common components in the six teas to the aroma, and the composition ratios of dominant compounds could be deemed as the critical factor that influences the aroma type of each tea.
谢关华,陆安霞,欧阳珂,等. GC-MS结合化学计量学用于探究六大茶类香气形成的差异[J]. 食品与发酵工业, 2021, 47(20): 260-270.
XIE Guanhua,LU Anxia,OUYANG Ke,et al. Analysis of the aroma formation in six categories of teas by GC-MS combined with chemometrics[J]. Food and Fermentation Industries, 2021, 47(20): 260-270.
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