Start with whole leaves, either loose tea or in tea bags that maintain the integrity of the leaves. The flavor of these teas evolve with each steeping rather than mass-produced tea bags that are usually made from chopped leaves, fannings, or tea dust. The strength of brewed tea depends on the ratio of leaves to water. Since each tea varies in weight, we recommend that you weigh leaves rather than measure them when brewing.
Use filtered water that is neither too hard nor soft, and pay close attention to temperature. Highly oxidized teas (oolong and black) need hot water to "wake up" the leaves (about 200°F), while green and white teas should have water that isn't as hot (about 175°F) to avoid activating bitter tannins or other cooked flavors.
Adjust your brewing time based on the size of your vessel and amount of leaves used. Generally, when using hotter water, steep the leaves for less time. You may want to steep green and white teas for longer in lower temperature water. The complexity and quality of whole-leaf teas allow for multiple steepings.
The type of vessel you use can be based on the type of tea you like to drink, or what is available. Glass and ceramic teaware is good for a variety of teas, while a clay pot is recommended if you drink one tea most often. Keep in mind that the size of your pot will determine the water to leaf ratio and steeping time.
The chemistry of tea is complex. Some of the primary compounds may impact people differently, depending on each individual's system and sensitivity to stimulants and enzymes.
Caffeine is a stimulant found in coffee, tea, chocolate, and other products. Tea generally contains less caffeine than coffee (20-90mg in a cup of tea vs. 100-200mg in a cup of coffee). The amount of caffeine in tea is based on a number of variables including the plant varietal (more durable leaves tend to have more caffeine); the age of the source plant (older plants have more caffeine); the harvest season (later flushes generally have more caffeine); amount of sunlight (sunlight encourages caffeine production); age of the leaves (leaves picked later have more caffeine); and the brewing method/temperature of the water used to infuse tea (hotter water increases the caffeine level). The general amount of caffeine in a cup of each type of tea is as follows:
Polyphenols are a compound of antioxidants that include flavonoids (tannins) that contribute to the bitter flavor of tea, and anthocyanin. These compounds - like wine - determine the tea's infusion, aroma, complexity, mouthfeel, and flavor.
L-Theanine is a rare amino acid that increases the production of alpha waves in the brain. L-theanine, in combination with caffeine, may improve brain function and contributes to the more mellow, relaxing effect produced by drinking tea versus coffee. These amino acids give tea its umami flavor, and tea is one of only three natural sources of theanine.
Enzymes, in particular polyphenol oxidase and peroxidase, contribute to the browning of the leaves when exposed to oxygen. The deactivation of these enzymes using heat is a key process in tea production.
Tea leaves also contain chlorophyll, aroma compounds, and several minerals including fluorine and potassium. Additionally, herbal teas may contain spices, flowers, and herbs that have a variety of properties.