Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin. EGCG, the most abundant catechin in tea, is a polyphenol under basic research for its potential to affect human health and disease. It is found mainly in white tea, green tea and, in smaller quantities, black tea; during black tea production, the catechins are mostly converted to theaflavins and thearubigins. It is also found in various vegetables, nuts, as well as carob powder at 109 mg per 100g. In a high temperature environment, an epimerization change is more likely to occur; however as exposure to boiling water for 30 straight minutes leads to only a 12.4% reduction in the total amount of EGCG, the amount lost in a brief exposure is insignificant. In fact, even when special conditions were used to create temperatures well above that of boiling water, the amount lost increased only slightly. EGCG is used in many supplements.