Heat is an integral part of the process of making many varieties of tea, with the amount of heat applied varying according to the type of tea. There are some varieties of tea that go through another stage of firing, one that qualifies them to be known as roasted tea. While many of these teas are commercially available, there are some enthusiasts who will actually go to the trouble of roasting their own leaves.
Among the best known of all roasted teas are the green varieties that are produced in Japan. Some of the most popular of these are Hojicha and Kukicha. Hojicha is a roasted tea made from the leaves of a green tea known as Bancha. The latter is considered by many to be one of the lower grades of Japanese green tea.
Kukicha is unusual in that it’s mostly produced from the stems, stalks, and twigs of the tea plant, rather than the leaves. As a result of the roasting process and the fact that the former tea uses less leaves, Kukicha and Hojicha are thought by some to be lower in caffeine content. The tea used in Genmaicha is not typically roasted, but it is worth noting here because it contains roasted rice. This gives it a distinctive flavor that some people like to compare to popcorn.
For some tea lovers, tinkering around with the process of roasting tea leaves can open up new ranges of flavor or may help to revive tea that’s past its prime. For some input from the tea community on this process refer to this post from the Tea Obsession blog, and this one, from the Hou De Tea blog, about using a commercially produced tea roaster.
Japanese researchers have gone so far as to study the effects of a variety of methods of roasting on the flavor of green teas. Another group of Japanese researchers took a look at the effects of roasting on antioxidant levels in green, black and oolong teas.
William’s blog, Tea Guy Speaks, is full of useful tea-related information!