Taste of tea

Besides the aroma, the taste quality is also one of the key criteria used by tea tasters to describe the quality of tea liquor.

Green tea, oolong tea and black tea all have their own distinctive flavors. Its taste is at first bitter and astringent and then sweet.

The balance of astringency, bitterness and brothy taste is important to the characteristic taste of tea; catechins and caffeine are counted as the major contributors to astringency and bitterness.

The major catechins in green tea are EGCg, ECg, EGC, and EC, which are classified as either gallate-type catechins (EGCg and ECg) or non-gallate type catechins (EGC and EC) by the presence of galloyl group on the oxygen atom at the C3 position.

Human perceive the taste of the gallate-type catechins to be more bitter astringent than that of the non-gallate type catechins.

Black tea and green tea are different in flavor due to the fermentation process during production of black tea, in which catechins are oxidized and polymerized to form theaflavins; and consequently the astringent taste of green tea is replaced with more complex astringent taste.

Theaflavin constituting about 0.3 – 1.8% of black tea dry weight and 1- 6 % of the solid in tea infusion. It contributes significantly to the bright color and brisk taste of tea infusions.

During a few minutes infusion, catechins from tea leaves are not fully extracted. The preparation method will affect the extraction efficacy and consequently the content of polyphenols in the cup.
Taste of tea