Tea pocket

A tea bag is a small, porous, sealed bag containing dried plant material, which is immersed in boiling water to make a tea or a infussion. Classically these are tea leaves (Camellia sinensis), but the term is also used for herbal teas (tisanes) made of herbs or spices. Tea bags are commonly made of filter paper or food-grade plastic, or occasionally of silk. The bag contains the tea leaves while the tea is steeped, making it easier to dispose of the leaves, and performs the same function as a tea infuser. Some tea bags have an attached piece of string with a paper label at the top that assists in removing the bag while also displaying the brand or variety of tea.

In countries where the use of loose tea leaves is more prevalent, the term "tea bag" is commonly used to describe paper or foil packaging for loose leaves. They are usually square or rectangular envelopes with the brand name, flavour and decorative patterns printed on them.

In China, during the Tang Dynasty (618–907), paper was folded and sewn into square bags to preserve the flavor of tea.

The first Western tea bags were hand-sewn fabric bags; tea bag patents date as early as 1903. First appearing commercially around 1904, tea bags were successfully marketed about 1908 by the tea and coffee importer Thomas Sullivan from New York, who shipped his silk tea bags around the world. The loose tea was intended to be removed from the bags by customers, but they found it easier to brew the tea with the tea still enclosed in the porous bags. Modern tea bags are usually made of paper fiber. The heat-sealed paper fiber tea bag was patented in 1930 by William Hermanson, one of the founders of Technical Papers Corporation of Boston, who sold his patent to the Salada Tea Company.

The rectangular tea bag was not invented until 1944. Prior to this, tea bags resembled small sacks.

A broad variety of teas as well as other infusions like herbal teas, are available in tea bags. Typically, tea bags use fannings, the left-overs after larger leaf pieces are gathered for sale as loose tea, but some companies sell teabags containing whole-leaf tea.

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Wikipedia