Matcha is finely ground powder of specially grown and processed green tea. It is notable in two aspects of its farming and processing. First the green tea plants for matcha are shaded for about three weeks before harvest which changes the flavor and exact composition of the leaves. Second, the stems and veins are carefully removed in processing. Processing is confined to drying and then grinding. Unlike black tea there is no fermentation step so the powder is a true reflection of the original plant material. Matcha tea contains high levels of a unique, potent class of antioxidants called catechins, which aren’t commonly found in other foods. In particular, the catechin EGCg (epigallocatechin gallate) has been shown to exhibit a potent antioxidant effect and is the subject of a great deal of research into its potential as a therapeutic agent.