EGCG

EGCG is the superstar of tea polyphenols, comprising 50-80% of total catechin content in green tea. As the most potent antioxidant in the catechin family, its free-radical scavenging capacity is 25-100 times greater than vitamins C and E. Research has linked EGCG to a wide range of potential health benefits: enhanced fat oxidation during exercise, improved insulin sensitivity, reduced LDL cholesterol oxidation, and inhibited growth of certain cancer cell lines in laboratory settings. EGCG concentration varies dramatically by tea type and processing: green tea retains the most because minimal oxidation preserves catechins intact. Steaming (Japanese method) preserves slightly more EGCG than pan-firing (Chinese method). Black tea and oolong contain less EGCG because oxidation converts catechins into theaflavins and thearubigins. Brewing parameters matter enormously — EGCG extraction increases with temperature and time, peaking at around 5 minutes in boiling water. However, this also increases bitterness, since EGCG is the primary contributor to tea's astringent taste. A 3-minute steep at 80 C provides a reasonable balance between EGCG extraction and palatable flavor.