Effects of withering and mass-rolling processes on the formation of aroma components in pouchong type semi-fermented tea.

Abstract

Aroma concentrates from twelve tea samples, manufactured by different withering processes from three varieties of tea leaves, were prepared and qualitatively and quantitatively analyzed by GC and GC-MS. The individual effects of (1) solar-withering, (2) indoor-withering with shaking and turn over treatment and (3) additional mass-rolling on the development of aroma components were illustrated by a comparison of the aroma compositions among 12 tea samples.The combined effect of these processes showed an increase in the concentrations of 23 main components with few exceptions. Remarkable concentration increases of α-farnesene, nerolidol, jasmine lactone, benzyl cyanide and indole were recognized while that of linalool decreased.