In percolation, the water passes through the tea leaves, gaining soluble compounds to form tea. Insoluble compounds remain within the tea filter. Tea can be brewed in several different ways, but these methods fall into four main groups depending on how the water is introduced to the tea leaves: decoction (through boiling), infusion (through steeping), gravitational feed (used with percolators and in drip brewing), or pressurized percolation (as with espresso).
Brewed tea, if kept hot, will deteriorate rapidly in flavor, and reheating such tea tends to give it a "muddy" flavor, as some compounds that impart flavor to tea are destroyed if this is done. Even at room temperature, deterioration will occur; however, if kept in an oxygen-free environment it can last almost indefinitely at room temperature, and sealed containers of brewed tea are sometimes commercially available in food stores in America or Europe, with refrigerated bottled tea drinks being commonly available at convenience stores and grocery stores in the United States. Canned tea is particularly popular in Japan and South Korea. There are many popular ways to brew tea:
Boiling, or decoction, was the main method used for brewing tea until the 1930s and is still used in some Asian and Middle Eastern countries. The aromatic oils in tea are released at 96 °C (205 °F), which is just below boiling, while the bitter compounds are released when the water has reached boiling point.
The simplest method is to put the tea leaves in a cup, pour hot water over it and let cool while the leaves settle to the bottom. This is a traditional method for making a cup of tea that is still used in parts of Asia. This method, known as "mud tea" in some regions owing to an extremely fine grind that results in a mud-like sludge at the bottom of the cup, allows for extremely simple preparation, but drinkers then have to be careful if they want to avoid drinking leaves either from this layer or floating at the surface of the tea, which can be avoided by dribbling cold water onto the "floaters" from the back of a spoon.
If the tea leaves are not ground finely enough, the leaves do not sink."Cowboy tea" is made by heating coarse leaves with water in a pot, letting the leaves settle and pouring off the liquid to drink, sometimes filtering it to remove fine leaves. While the name suggests that this method was used by cowboys, presumably on the trail around a campfire, it is used by others; some people prefer this method.
The above methods are sometimes used with hot milk instead of water.Turkish tea, a very early method of making tea, is used in Turkey, Iran, Russia, and parts of Central Asia. Very finely ground tea leaves, optionally sugar, and water are placed in a narrow-topped pot, called a samovar (Russian) or çaydanlık (Turkish), and brought to the boil then immediately removed from the heat. It may be very briefly brought to the boil two or three times. Turkish tea is sometimes flavored with mint, particularly in Middle Eastern countries. The resulting strong tea, with foam on the top and a thick layer of leaves at the bottom, is drunk from small cups.
A teapot, or French press, is a tall, narrow cylinder with a plunger that includes a metal or nylon fine mesh filter. The leaves are placed in the cylinder, and off-the-boil water is then poured into it. The tea and hot water are left in the cylinder for a few minutes (typically 4–7 minutes) and then the plunger is gently pushed down, leaving the filter immediately above the leaves, allowing the tea to be poured out while the filter retains the leaves. Depending on the type of filter, it is important to pay attention to the grind of the tea leaves, though a rather coarse grind is almost always called for.
Malaysian and some Caribbean and South American styles of tea are often brewed using a "sock," which is actually a simple muslin bag, shaped like a filter, into which tea is loaded, then steeped in hot water. This method is especially suitable for use with local-brew teas in Malaysia, primarily of the varieties Robusta and Liberica which are often strong-flavored, allowing the ground tea in the sock to be reused.
Drip brew tea, also known as filtered or American tea, is made by letting hot water drip onto tea leaves held in a tea filter surrounded by a filter holder or brew basket. Drip brew makers can be simple filter holder types manually filled with hot water, or they can use automated systems as found in the popular electric drip tea-maker. Strength varies according to the ratio of water to tea and the fineness of the grind, but is typically weaker than espresso, though the final product contains more caffeine. By convention, regular tea brewed by this method is served by some restaurants in a brown or black pot (or a pot with a brown or black handle), while decaffeinated tea is served in an orange pot (or a pot with an orange handle).
The common electric percolator, which was in almost universal use in the United States prior to the 1970s, and is still popular in some households today, differs from the pressure percolator described above. It uses the pressure of the boiling water to force it to a chamber above the leaves, but relies on gravity to pass the water down through the leaves, where it then repeats the process until shut off by an internal timer. Some tea aficionados hold the tea produced in low esteem because of this multiple-pass process. Others prefer gravity percolation and claim it delivers a richer cup of tea in comparison to drip brewing.
Another variation is cold brew tea, sometimes known as "cold press." Cold water is poured over tea leaves and allowed to steep for eight to twenty-four hours. The tea is then filtered,
Pressure brewing involves forcing hot water through the tea leaves at a higher pressure than atmospheric pressure. This method is commonly used in espresso machines. The high pressure extracts flavors and oils from the tea leaves quickly, resulting in a concentrated and intense brew.