Black tea is the most intensively processed type of tea. The leaves are allowed to fully oxidize, creating their black color before they are dried, giving black tea more complexity, more astringency and fewer vegetal overtones than are typically found in other teas. Astringency is the "dry mouth" sensation left by tannins in tea, familiar to drinkers of a cabernet sauvignon, or other wine. It is this astringency that pairs so nicely with dairy and sweetener. Achieving the right balance of astringency is one of the leading indicators of quality in a black tea.