The basics of tea
what is tea?
Tea, put simply, is a drink made from infusing the dry leaves, buds and stems of the Camellia sinensis plant. More specialist teas, like authentic jasmine tea, are infused with the scent of flower petals. 100% herbal and floral teas are not strictly teas, but tisanes or infusions as they do not have leaves from the Camellia sinensis tea plant. However the most popular herbal infusions are commonly referred to as say Chamomile tea and Mint tea.
Camellia sinensis is an evergreen plant that grows in tropical and sub-tropical climates between 1200 and 1500 metres above sea level. There are two main varieties commonly used for tea; Camellia sinensis (the native Chinese tea bush) and Camellia sinensis assamica (the native tea bush of India), plus thousands more subspecies of each type.
The taste and appearance of tea depends on many different factors. If you want to know what makes really delicious tea delicious, keep reading.
the tea variety
There are over 3,000 hybridised cultivars (fancy word for a plant type that’s been selectively bred) within the China tea group, each with unique characteristics that make them appropriate for the production of particular teas. Some varieties have been created to suit particular climates, soils and altitudes, whereas others have been bred to make one specific type of tea. Most oolong teas for example, like Da Hong Pao (Big Red Robe) and Dan Cong, are made from unique cultivars. Other varieties, like the large-leaved ‘Great White’ is mostly used to make white teas (unsurprising), but can also be processed into green or some oolong teas.
Teas picked in spring usually have different characteristics from those harvested in autumn. Some teas – green and whites for the most part – are generally only picked in the spring, while some oolongs have four harvests and span the seasons.
You’ve probably heard terroir in relation to wine, but it applies to tea too. In short, terroir means the geography of the place in which the tea is grown and consists of three elements: soil, climate and topography. The most delicious teas are grown between 600 and 1500 metres in relatively acidic soil – high altitudes mean slower growth, which means more flavour. The Chinese generally believe that the poorer soil in high mountain regions, such as Wuyi Shan, produces the best tea in the world. If you want to get specific, really good tea needs tropical and subtropical climates (i.e. warm days and relatively cool nights) that average at least 1500mm of rain per year. In the right conditions, the slower the leaves grow, the more defined and complex the tea will be.
When it comes to picking the tea leaves or buds, timing is absolutely critical. So too is the skill of the pickers. In India and China the best teas are picked by hand, often bio-dynamically, which means the tea is picked according to phases of the moon. In most cases, only the tips or the flushes (i.e. new growth leaves) of the tea bush are picked, and the timing and technique depends on the category of tea being made. For example, Silver Needle white tea is made from just the top unopened leaf bud, whereas oolong is made with two leaves and a bud.
The way that the tea is processed all depends on the type of tea being made. The best teas are processed laboriously by hand, by artisan tea farmers whose skills have been honed over generations of family tea farmers. As soon as tea is picked it starts to oxidise, turning from green to brown. The level of oxidation depends on the type of tea required. White tea is dried slowly at low temperatures, allowing only very light, partial oxidation; green teas are kept green and unoxidised by being heated immediately after picking to kill the enzymes in the leaf which would otherwise react and oxidise on contact with air. With oolong and black teas the leaves are bruised and rolled or pressed to allow partial or full oxidation. In each case the skill of the tea-maker is critical to release the catechins, the antioxidant flavonoids (or compounds) that determine the flavour profile of each tea.
Brewing techniques can make or break a good tea tea. Water quality and temperature, the type of brewing vessel, the length and number of infusions, and proportion of tea to water are all critical to the taste and quality of the infusion. Every good tea supplier will give suggested parameters on how to get the best from the leaf, but as a general rule green teas always need to be brewed with cooler water approx 75°C, even cooler for Japanese green teas, white teas around 80°C, oolongs from 80-90°C depending on whether they are lightly oxidised or heavily oxidised, and black teas can be brewed hotter around 95°C, near-boiling water. Chinese Puerh teas are brewed hot and quick in a small Yixing (aka Zi Sha) clay teapot. This material complements and enhances the complex flavours of the tea, but this is a whole other story.
Although there is a certain amount of personal preference when it comes to how you like your tea, there is no doubt that brewing tea according to some basic guidelines can transform your experience.
For instance, brewing a delicate green tea too hot will extract the bitter compounds from the leaf and overwhelm the subtle flavour notes. Reducing the temperature of the water will draw out the fragrant aroma and the desirable flavour notes such as fresh green bean, nuts and honey without any hint of bitterness.
Exploring new teas and experimenting with the leaf to water ratio, the temperature of the water and the steeping time are all part of the experience with tea. But be careful, once you get a taste for fine tea, there’s no going back.