Both black and
green tea is harvested from an evergreen, tree-like shrub known as
camellia sinensis. Most likely originating in China, the camellia
sinensis is thought to have first been used to brew a medicinal
drink during the Shang Dynasty (1600 BC to 1046 BC). By the third
century BC, it had become a relatively popular drink using only the
leaves from this plant, rather than mixed with other things as was
common when used medicinally.
Leaves that are going to be used for black tea are allowed to
ferment, or oxidize, completely. The general process is to roll,
tear, or crush the leaves to help the oxidation process (similar to
why the inside of an apple turns brown when exposed to air). The
leaves are then dried out, sometimes in the sun or using machines.
As the leaves oxidize, they gradually turn from green to black.
Manufacturers create green tea by picking the leaves off the plant
and then heating them immediately. This is commonly done by pan
firing the leaves or steaming them. Heat stops the leaves from
oxidizing and allows them to maintain their green color.
Oolong tea is initially generally processed in the same way as black
tea, but is not allowed to oxidize for as long. Once the desired
oxidation level has been reached, which varies by type and
manufacturer (some oolong tea is closer to green tea, while others
are closer to black), the leaves are fired similar to green tea to
stop the oxidation process at that point.
White tea is made by picking the leaves and buds early in the year
while the bud is still closed. The leaves may be placed out to dry
in the sun or mechanically, and minimizing oxidation.
Highest tea consumption per person per year, as of 2014:
1 Turkey 6.87 kg (242 oz)
2 Morocco 4.34 kg (153 oz)
3 Ireland 3.22 kg (114 oz)
4 Mauritania (Africa) 3.22 kg (114 oz)
5 United Kingdom 2.74 kg (97 oz).
A cup of tea is generally six ounces.