The typical tea drunk around the world is made from a Camellia.
But not just any Camellia, the Chinese Camellia.
Camellia sinensis is the species of plant whose leaves and leaf buds are used to produce the popular beverage tea. It is of the genus Camellia (Chinese: 茶花; pinyin: Cháhuā, literally: “tea flower”), a genus of flowering plants in the family Theaceae. White tea, green tea, oolong, pu-erh tea and black tea are all harvested from this species, but are processed differently to attain different levels of oxidation. Kukicha (twig tea) is also harvested from Camellia sinensis, but uses twigs and stems rather than leaves. Common names include tea plant, tea shrub, and tea tree (not to be confused with Melaleuca alternifolia, the source of tea tree oil).
I’ve occasionally thought of getting Camellia Sinensis and growing my own tea in the yard. We have a suitable climate for it here. I can even order seeds:
About 42 cents per seed. (and not a lot of information about cultivar…)
These things grow well, but it would still take a couple of years to reach a point where I could figure out if I liked making my own and practice the techniques. So I’ve occasionally asked at nurseries around here if they could order one for me. Usually that ends in a long discussion about “No, I do not want the Camellias you have all over the back wall, they are not the Camellia I am looking for…”
So I’d begun to give up on getting a tea bush. After all, it takes a particular camellia.
Or so I thought…
Camellia sinensis, the tea plant, is of major commercial importance because tea is made from its leaves. While the finest teas are produced by C. sinensis courtesy of millennia of selective breeding of this species, many other camellias can be used to produce a similar beverage. For example, in some parts of Japan, tea made from C. sasanqua leaves is popular.
Hang on a minute, I’m thinking…. I have a large Camellia bush in the back yard…
So at some point, probably soon since ‘harvest’ is in early spring or late spring, I’m going to try making some beverage tea out of my “decorative” camellia bush. The bunnies love to nibble down a few leaves, especially when they look a bit tired, so I figure it likely “has the good stuff” in it somewhere.
Processing looks ‘not too hard’ but takes a bit of time. Pick, dry / wilt, cook, ferment, torture, dry… Fire must be involved somewhere, so I’m good with that ;-)
The wiki seems to cover it, though perhaps with way too many variations for what I really need.
Green tea looks very easy (nearly trivial..)
The ancient Chinese society first encountered the tea plant in what is now southern China and processed it as another medicinal herb for use in Chinese herbology. The processing technique used to process fresh tea leaves was to immediately steam the fresh tea leaves and dried them for preservation. This method is likely the most ancient Chinese form of tea leaf processing that was perfected around near the end of the Han Dynasty (206BCE-220CE, which results in a product that would be classified today as “green tea” (緑茶) and quite similar to modern Japanese sencha. For consumption, dried tea leaves were either decocted with water around with other herbs, or ground into a powder to be taken straight or in a liquid.
So basically pick, steam, dry. There are several other specialty teas with a variety of degree of several of the steps below, including those for black tea. If anyone really needs to make “yellow tea” or the others, hit the wiki.
“Tea leaf processing methods for the six most common types of tea”
Black tea is that red line of blocks at the bottom. Not too complicated either. Click for a much larger version.
Although each type of tea has different taste, smell, and visual appearance, tea processing for all tea types consists of a very similar set of methods with only minor variations. Without careful moisture and temperature control during its manufacture and life thereafter, fungi will grow on tea. This form of fungus causes real fermentation that will contaminate the tea and may render the tea unfit for consumption.
Plucking: Tea leaves and flushes, which includes a terminal bud and two young leaves, are picked from Camellia sinensis bushes typically twice a year during early spring and early summer or late spring. Autumn or winter pickings of tea flushes are much less common, though they occur when climate permits. Picking is done by hand when a higher quality tea is needed, or where labour costs are not prohibitive. Depending on the skill of the picker, hand-picking is performed by pulling the flush with a snap of the forearm, arm, or even the shoulders, with the picker grasping the tea shoot using the thumb and forefinger, with the middle finger sometimes used in combination. Tea flushes and leaves can also be picked by machine, though there will be more broken leaves and partial flushes reducing the quality of the tea. However, it has also been shown that machine plucking in correctly timed harvesting periods can produce good leaves for the production of high quality teas.
Withering/ Wilting: The tea leaves will begin to wilt soon after picking, with a gradual onset of enzymatic oxidation. Withering is used to remove excess water from the leaves and allows a very slight amount of oxidation. The leaves can be either put under the sun or left in a cool breezy room to pull moisture out from the leaves. The leaves sometimes lose more than a quarter of their weight in water during withering. The process is also important in promoting the breakdown of leaf proteins into free amino acids and increases the availability of freed caffeine, both of which change the taste of the tea.
Disruption: Known in the Western tea industry as “disruption” or “leaf maceration”, the teas are bruised or torn in order to promote and quicken oxidation. The leaves may be lightly bruised on their edges by shaking and tossing in a bamboo tray or tumbling in baskets. More extensive leaf disruption can be done by kneading, rolling, tearing, and crushing, usually by machinery. The bruising breaks down the structures inside and outside of the leaf cells and allows from the co-mingling of oxidative enzymes with various substrates, which allows for the beginning of oxidation. This also releases some of the leaf juices, which may aid in oxidation and change the taste profile of the tea.
Oxidation / Fermentation: For teas that require oxidation, the leaves are left on their own in a climate-controlled room where they turn progressively darker. This is accompanied by agitation in some cases. In this process the chlorophyll in the leaves is enzymatically broken down, and its tannins are released or transformed. This process is sometimes referred to as “fermentation” in the tea industry. The tea producer may choose when the oxidation should be stopped, which depends on the desired qualities in the final tea as well as the weather conditions (heat and humidity). For light oolong teas this may be anywhere from 5-40% oxidation, in darker oolong teas 60-70%, and in black teas 100% oxidation. Oxidation is highly important in the formation of many taste and aroma compounds, which give a tea its liquor colour, strength, and briskness. Depending on the type of tea desired, under or over-oxidation/fermentation can result in grassy flavours, or overly thick winey flavours.
Fixation / Kill-green: Kill-green or shāqīng (殺青) is done to stop the tea leaf oxidation at a desired level. This process is accomplished by moderately heating tea leaves, thus deactivating their oxidative enzymes and removing unwanted scents in the leaves, without damaging the flavour of the tea. Traditionally, the tea leaves are panned in a wok or steamed, but with advancements in technology, kill-green is sometimes done by baking or “panning” in a rolling drum. In some white teas and some black teas such as CTC blacks, kill-green is done simultaneously with drying.
Sweltering / Yellowing: Unique to yellow teas, warm and damp tea leaves from after kill-green are allowed to be lightly heated in a closed container, which causes the previously green leaves to turn yellow. The resulting leaves produce a beverage that has a distinctive yellowish-green hue due to transformations of the leaf chlorophyll. Through being sweltered for 6–8 hours at close to human body temperatures, the amino acids and polyphenols in the processed tea leaves undergo chemical changes to give this tea its distinct briskness and mellow taste.
Rolling / Shaping:The damp tea leaves are then rolled to be formed into wrinkled strips, by hand or using a rolling machine which causes the tea to wrap around itself. This rolling action also causes some of the sap, essential oils, and juices inside the leaves to ooze out, which further enhances the taste of the tea. The strips of tea can then be formed into other shapes, such as being rolled into spirals, kneaded and rolled into pellets, or tied into balls, cones and other elaborate shapes. In many types of oolong, the rolled strips of tea leaf are then rolled to spheres or half spheres and is typically done by placing the damp leaves in large cloth bags, which are then kneaded by hand or machine in a specific manner.
Drying: Drying is done to “finish” the tea for sale. This can be done in a myriad of ways including panning, sunning, air drying, or baking. Baking is usually the most common. Great care must be taken to not over-cook the leaves. The drying of the produced tea is responsible for many new flavour compounds particularly important in green teas.
Aging / Curing: While not always required, some teas required additional aging, secondary fermentation, or baking to reach their drinking potential. For instance, a green tea puerh, prior to curing into a post-fermented tea, is often bitter and harsh in taste, but becomes sweet and mellow through fermentation by age or dampness. Additionally, oolong can benefit from aging if fired over charcoal. Flavoured teas are manufactured in this stage by spraying the tea with aromas and flavours or by storing them with their flavorants.
I think I’ll start with green tea…