All tea comes from the leaves of one plant, Camellia sinensis, which is processed into four tea types:

White, Green, Oolong and Black.

Local conditions in the various tea-growing regions of the world determine a tea's characteristics, and one tea type can be quite different from another of its type in colour, body, flavour and aroma.

In addition to teas from the tea bush, hot-water infusions made from herbs are also called "tisanes" or "teas." There are many flavorful and efficacious herbs, which are used to flavour. This include ginger, chemomile, peppermint etc.

In the case of White Tea, the difference comes from which part of the plant or variety/ clone is used. Green, Oolong and Black Teas all come from the upper leaves of Camellia sinensis, while White Tea may only consist of leaves from the branch tips--particularly the leaf bud and possibly the first two leaves under the bud.

Additionally, in many countries leaf for White Tea is picked once a year in the spring and is thus less available than the others.

In Kenya, leaf for white tea can be picked throughout the year though from specific hairy (with trichomes) clones such as AHP s 15/10.

For all four teas, the main point differentiating them comes from processing. After being picked from the Camellia sinensis plant, both White and Green Teas remain as unoxidized teas, Oolong tea is partially oxidized, and Black Tea is fully oxidized. Oxidation occurs when enzymes in the tea leaves are released due to maceration and the leaf responds to the oxygen in the environment, causing the leaves to turn a bright copper colour.

In specific, White Tea is minimally processed--the leaves are only lightly steamed or, sometimes, just dried. In Green Tea, the leaves are steamed and/or pan fired, then they are rolled and dried. Leaves for Oolong Tea are partially oxidized (more than Green Tea, less than Black Tea), then dried. Black Tea is fully oxidized. This processing--all from the leaves of the same plant--is what gives tea types their differences in names and flavours.

Basically, processing gives Black Teas a more full-bodied and robust taste and Green Teas a more delicate, fresh taste, while Oolong Teas fall somewhere in between. Since only the tips are used and the processing is minimal, White Tea has the most delicate flavour of all.

Since all teas are produced from Camellia sinensis, they naturally contain caffeine. Different varieties or clones have different caffeine levels in their pluckable shoots and will therefore influence the level of caffeine in tea processed from them . Processing other than decaffeination does not change the caffeine content. All teas have approximately the same amount of caffeine, falling within a range of 25 to 60 mg of caffeine in a 6-oz. cup. For comparison,Coffee has about 100 mg per 6 ounces.

Processed tea can be further decaffeinated to remove the caffeine. Decaffeination is carried out through a process using carbon dioxide and water. Other common decaffeination process use ethyl acetate .The use of co₂ in decaffeination results in a higher percentage of nutrients remaining in the tea leaves.further,no residues are left in the decaffeinated tea with co_2.

Black Teas should be infused with water that has just come to a boil—approximately

85-90 degrees centigrade. It can be steeped 3 to 5 minutes, depending on the cut of the leaf. Whole leaves need to be steeped longer than smaller cuts such as those found in CTC Teas.

Tea is among the richest natural sources of antioxidants, which have been linked with cancer prevention, decreased risk of stroke, and reduced blood cholesterol. Additionally, it has trace amounts of various nutrients such as the amino acid theanine; the minerals calcium, magnesium, manganese and potassium; and the vitamins C and K.

Naturally occurring antioxidants are nutrients found in most plants, including fruits and vegetables.

They bind free radicals and peroxides--both of which are oxygen-containing molecules in your body that, if left unchecked, can damage your DNA, cell membranes and other cell components. The process of breaking down food for energy creates free radicals and peroxides in your body everyday.

Antioxidants help your body keep these harmful substances in check.

All teas contain antioxidants, including a class called flavonoids, which are found in most plants common in the human diet. Of the more common flavonoids, Green Teas contain more of the simple flavonoids called catechins, while the oxidization that the leaves undergo to make Black Tea converts these simple flavonoids to the more complex varieties called theaflavins and thearubiginsCatechins,theaflavins and thearubins, have antioxidant activity.

Yes, Research has shown that antioxidants are equal in brewed Black Teas whether they are hot or iced--but not necessarily in instant teas because some of the antioxidants are lost during the additional processing.

Sugars, sweeteners, lemon and milk may not affect the antioxidant levels of Black Tea flavonoids.However ,too much milk may bind the antioxidants in tea and make them less available for absorption.

No. Though all teas contain high levels of potent antioxidants, it is still important to eat a

Well-balanced diet. Fruits and vegetables offer vital sources of vitamins, minerals, fiber and various antioxidants not found in other food groups in the human diet.