Posted by Arbor Teas on November 29, 2007
Many people don't realize that all types of tea begin with the leaf from a single plant, Camellia sinensis. It is actually the manner in which the tea leaf is processed after it is picked that determines whether it becomes white, green, oolong, black, or pu-erh tea. Tea can be manufactured using one of two approaches, orthodox or CTC. Orthodox production methods, whether done by hand or by machine, generally preserve the integrity of the tea leaf and involve significant human attention. By contrast, CTC manufacturing (short for “crush-tear-curl”) uses machines to mince, shred or crush the leaf. Both methods can produce excellent teas; however the orthodox method is typically considered the more “traditional,” and produces tea that is generally more complex in flavor and aroma.
Orthodox manufacture begins by selectively picking (often by hand) tea leaves. The leaves are allowed to wither, reducing their water content and making them soft and pliable. Once withered, the leaves are gently rolled to break down the cellular structure, beginning the oxidation process. The oxidation stage is primarily responsible for differentiating tea into its various categories – white, green, oolong, and black - and determining tea's caffeine content. The longer the oxidation process is allowed to continue, the darker the leaf becomes, and the more caffeine the tea contains. White teas are not rolled or oxidized at all. Once the desired level of oxidation is reached, the leaves are dried to halt the oxidation process and make them suitable for distribution. The dried leaves are then graded and sorted into various sizes: whole leaf, broken leaf, fannings (small particles) and dust.
CTC (Crush-Tear-Curl) is the most well known non-orthodox method of manufacture, and was invented during WWII to increase the weight of the tea that could be packed into a chest. It also eliminates some of the labor required to produce tea, thus increasing the speed and efficiency of tea manufacture. In the Crush-Tear-Curl process, tea leaves are plucked and withered. After they are withered the tea leaves are passed through a series of cylindrical rollers that crush, tear and roll the tea leaves into tiny, irregular balls that somewhat resemble coffee grounds. Once completed, the leaves are left to oxidize and are finally fired. After the tea is fired, it is sorted into different grades. CTC tea is used primarily in mass-market teabags. Given the small particle size, CTC tea has a greater surface area ratio than whole leaf tea, causing it to brew quickly and generally have a thicker body with more astringency.