Enhancement of Black Tea Aroma by Adding the <i>β</i>-Glucosidase Enzyme during Fermentation on Black Tea Processing

Black tea aroma is one of the essential attributes in determining the quality of black tea. beta-Glucosidases were investigated for their ability to enhance the aroma of black tea by hydrolyzing the glycoside compound. The addition of beta-glucosidase was done by dissolving the enzyme on a sodium citrate buffer (pH 5.0), which was then sprayed on tea leaves during black tea processing. The beta-glucosidase treatment significantly increases the volatile compound from glycoside precursors such as linalool, geraniol, and methyl salicylate. Moreover, the volatile compound from carotenoid and lipid precursors (nerolidol and beta-cyclocitral) was also increased with beta-glucosidase treatment.