Tea Types and Processing
All tea comes from one plant, Camellia sinensis. If it doesn't come from this plant, it is not tea in the true sense of the word. Tisanes, or herbal teas as they are better known, come from a variety of plants and therefore are not “tea”.
Teas are grown in different regions around the world. The most widely recognized are China, Japan and India. When tea leaves are harvested, a natural oxidation, sometimes referred to as “fermentation”, begins to occur. This oxidation is environmental, not man made, and is halted by heating the tea leaves. This heating is done by firing or steaming the leaves. Oxidation, or the lack of oxidation, is the basic difference in tea types, i.e. green tea from black tea as illustrated in the chart below.
White and green teas are both harvested and then heated immediately making them non oxidized. They produce a fragrant, vegetal character, and when properly brewed the tea liquor will appear light and clear with a pale green or yellow hue. These delicate teas should never be prepared with boiling water.
Oolong teas are allowed to oxidize for various lengths of time (15– 75 percent oxidation) allowing for a wide range of character and caffeine content; the darker, or more oxidized, the higher the caffeine content. The most commonly consumed oolong teas in the US are the dark varieties, which appear amber in color and are rich and complex in taste. Whether light or dark, oolong teas are delicious and terrific for easing digestion and aid in healing skin disorders like eczema.
Black teas are allowed to fully oxidize giving them a rich, dark appearance, the greatest amount of caffeine and a strong, brisk flavor. Black teas are wonderful for preventing heart disease and stroke, and like their close relatives, green, white and oolong tea, provide us with many important antioxidants.
While this is a simplification of a somewhat complicated process, it outlines the basic processing and characteristic differences in the various tea types. All “tea” has healthful benefits; you just need to taste and explore to find the one that most appeals to you. Since there are over 3,000 different teas in the world you are sure to find one that is perfect for you; then, just drink to your health!