Ko-Cha Tea This page first published: Apr 19, 2005 · Updated: May 6, 2018 · by CooksInfo. Copyright © 2021 · This post may contain affiliate links · This blog generates income via ads · Ko-Cha is the Japanese word for “Black Teas” in general, such as is drunk by Westerners. If drunk with milk and sugar in it, it is called “miruku tei”; if drunk with lemon in it, it is called “remon tei.”