Black tea aroma is one of the essential attributes in determining the quality of black tea. β-Glucosidases were investigated for their ability to enhance the aroma of black tea by hydrolyzing the glycoside compound. The addition of β-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 β-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 β-cyclocitral) was also increased with β-glucosidase treatment.

PT. Pagilaran was developing five new clones that were named as PGL 9, PGL 10, PGL 11, PGL 12 and PGL 15 as superior clones for black tea. That clones are very potential to be used as ready to drink (RTD) instant tea beverages.  Ready to Drink (RTD) from black tea have a weakness, which was low antioxidant activity. Tannase was an industrial enzyme of the great potential for application in the food industry. Tannase has used to hydrolyze gallated ester green tea catechin. There was no study about the changes in chemical composition by tannase enzymatic treatment of PT Pagilaran’s tea clones.  The objectives of this study were to observe the effects of tannase treatment on five clones black tea extracts to the antioxidant activity,  profile of phenolic compounds, the tea brew color, consumer acceptance, and volatile compounds. Tea leaves of medium plucking were traditionally processed into black tea. The tea brew was added with tannase at a concentration of 100mg/100mL then incubating for 1 hour at a temperature of 37ºC.  Additional tannase tent to increase their antioxidant activities, the gallic acid, EC, and EGC concentrations due to hydrolysis of ECG, EGCG, or their derivatives. The color of tea brew was getting brighter and yellowing than untreated ones. Even so, the level of consumer acceptance was still good. Profile aroma and volatile compounds of tea brew showed that there were no significant changes after enzymatic treatment.

The manufacturing of ready-to-drink black tea was through a long process, up to 14-18 hours. There was an alternative way to produce RTD black tea directly on the farm to reduce time production and improve the quality of black tea using exogenous enzymes, i.e., tyrosinase and β-glucosidase. Tyrosinase was investigated for the ability to improve the color of tea extract by oxidize the phenolic content of green tea leaves to theaflavin and thearubigin, and β-glucosidase can enhance the volatile compounds by hydrolyze glycosidic bonds in tea leaves. Incubation of tea leaf extract with tyrosinase produces a high content of theaflavin and good color of tea extract but lowered the antioxidant activity. According to the TF/TR ratio values, tyrosinase treated tea leaf extract was in the best quality tea range. The use of β-glucosidase showed an increase in the proportion of good volatile compounds of linalool, linalool oxide, methyl salicylate, and β-damascenone.