Tea is defined as any combination of stems and/or leaves of the plant 'camellia sinensis' whereby those constituents undergo a refinement process of rolling and/or heating to yield a dry product which, when infused in hot water, produces a fragrant, consumable beverage.
Wondering what differentiates the many types of tea? Tea can loosely be classified according to degree of oxidation; black, oolong, or pu erh teas being oxidized, either partially or fully, where green, white, or yellow are unoxidized. Oxidation is often incorrectly referred to as "fermentation". As yellow tea is still quite rare, we do not cover it here.
After plucking, tea leaves are allowed to wilt, rendering them pliable. Leaves destined for black status are rolled - a processing step which allows enzymes and other constituents to combine with oxygen and form new components. If the process is not halted through heating, the leaves oxidize completely. Full oxidation gives the color and flavor to what we call Black tea (called 'red tea' in China).
Pictured above: Earl Grey
Green teas are the second least-oxidized teas. Although they are processed slightly differently from region to region, and the type of leaf used can vary, green teas all are made with one intention in mind: to keep the leaves green by preventing oxidation. Green teas are plucked, withered, heated (by steam or by roasting) to prevent oxidation, and rolled. Finally, the tea is dried and then sorted by quality.
Pictured above: Mao Jian Tranquility (Organic)
Oolong or Wulong teas are still relatively unknown in the west. But their popularity is growing. Oolongs are partially oxidized and are browner than green teas, yet greener than black teas. They are processed much like green and black teas, but are allowed to oxidize from 25% to 75%. They're plucked, withered, and then tossed, bruising the leaf and allowing oxidation to begin. When oxidation reaches a desired level, the leaves are heated to prohibit any further oxidation. Then they're sometimes twisted or rolled into nuggets. Finally, they're dried. Occasionally an oolong will be roasted again after drying to give it a toastier flavor and a darker brew.
Pictured above: House Blend Oolong
White tea is the least processed. This is where we will begin. White tea consists of the newest buds and leaves of the tea plant. The undersides of these young buds and leaves are covered with a downy white hair, thus giving the tea its name. The fresh buds are plucked, heated and dried. No oxidation occurs. The result is a lightly colored tea with silvery hairs and a mild flavor. The freshness and low yield of white teas often make them more expensive than traditional black or green teas.
Pictured above: Silver Needles
Are Herbal Teas really teas? By definition, no. Herbs and herbal blends used for infusion and drinking are not teas if they do not contain parts of the camellia sinensis plant. However, that does not stop much of the western world from referring to these highly popular and sometimes medicinal beverages as "tea". More accurately, these beverages should be called "tisanes" (tee-SAWNZ), "herbal blends", or "herbal infusions".
Pictured above: Feel Better Chamomile Blend (Organic)