Believe it or not, all tea comes from the same exact plant
“I always like to start with the fact that, be it white tea, green tea, black tea, or oolong, it all comes from the Camellia sinensis plant,” says Hattie. “There are two main kinds: the Camellia sinensis sinensis and Camellia sinensis assamica. The Camellia sinensis assamica grows more in India and Sri Lanka, as well as Kenya. The Sinensis sinensis varietal is the kind that you find throughout China, Vietnam, Korea, and Japan.”
Also known as the tea plant (of course), Camellia sinensis is a small evergreen shrub or tree. Its leaves and leaf buds are the parts that eventually wind up in your cup.
…which means herbal tea is not technically tea
Yep, you heard us right. Herbal tea is not really tea in the true sense of the word, as it doesn’t stem from the almighty Camellia sinensis. Instead, it’s usually a blend of leaves, roots, flowers, or bark from any number of edible plants. That’s not to say that steamy mug of soul-hugging Tension Tamer isn’t delicious — it’s just, you know, not actually tea.
It’s all about oxidation
Even though they originate from the same plant, anybody who’s tasted them knows that green tea, white tea, oolong, and black tea each have their own very distinct characteristics. That’s where oxidation comes in. After the harvester plucks off the leaves or buds, they process the clippings into the dried, steepable little packages we know and love. The amount of oxygen it’s exposed to during this process is what helps to determine the tea’s eventual classification.
“Coffee is a really good analog,” Hattie explains, putting it into more familiar terms. “Green tea, that’s kind of your light roast coffee. It’s very lightly steamed, just enough to kind of kill the enzymes and stop the oxidation process. That’s actually what we call the ‘kill green’ stage, because it keeps the leaf green. From there it’s rolled and heated until you have about 7% moisture content, then it’s packed and shipped.”
“Black tea, that’s more like your dark roast coffee,” she continues. “It’s been dried for a really long time, it’s been withered, it’s been rolled. It’s gone through a much more intense production process. The longer you do it, the more times you roll it before it’s fired, that’s going to determine whether it becomes oolong tea, which is less oxidized, or black tea.”
White tea is the youngest and most delicate
Green tea, black tea, and oolong are generally made out of the leaves of the plant. But white tea, that one’s special.
“White tea is the little baby buds,” says Hattie. “If you can imagine a fuzzy little pea shoot, that’s what a tea plant looks like when it’s just starting to be picked. Only the very first pick of the year can be considered really good quality white tea. You just pluck them between your fingers. It kind of looks like a tiny little butterfly pod or something. You pick that, and then process it similar to green tea.”
Because it’s plucked at such a young stage and undergoes little if any oxidation, white tea is prized for its soft, fresh-from-the-garden flavor and aroma.
Caffeine levels are relative
When it comes to figuring out which variety will give you the most pep in your step, looks can be deceiving.
“A lot of people associate black tea with being high in caffeine, but pound per pound it’s really not,” reveals Hattie. “Most tea companies in the West use a method called CTC or Cut-Tear-Curl, where the tea is basically ground up into the fineness of a tobacco, with all the leaves broken up into really small pieces. That makes for a much more intense steep and a really intense brew, but it’s just because there’s more leaves to water. When people drink green tea, it’s oftentimes the whole leaf, so you effectively get a little bit less caffeine but that’s because of surface area, not necessarily true caffeine content.”
Tea is loaded with healthy antioxidants
“All tea does contain antioxidants, but white, green, and black teas have different amounts,” Hattie says. “Green tea and white tea are highest in things like epigallocatechin or ECGC, which is a really potent antioxidant that you see in extracts and supplements.”
ECGC is a catechin, a type of phenolic compound that’s markedly high in antioxidant activity and therefore associated with a whole host of human health benefits, including improved cardiovascular and immune system functioning. Oolong and black tea are more heavily processed than their lighter siblings, so they’re considered to have slightly lower antioxidant levels, namely less ECGC, by the time they land in our cupboards.
Little known fact: Boiling water is not always best.
“If you want to improve your tea experience, experiment brewing with different water temperatures,” Hattie says. “So often when you go to a fast food place or restaurant and ask for anything other than black tea, it’s horrible. Like if you go to Tim Horton’s for a green tea, it’s pretty miserable. You’re thinking, ‘Why would anyone ever drink this?’
“But the truth is when you brew tea with different water temperatures, you bring out different aspects in the tea. Green tea actually burns really easily — the leaves are really delicate because they haven’t been processed very much. So when you steep it in boiling water right off the stove, you’re drawing out more of the tannins and more of the caffeine, all these dry and bitter elements, which is not what you want. You want these sweet vegetal notes, asparagus and steamed greens, things like that. With cooler water, say around like 80 or 85 degrees Celsius, you get all those nice components.”
The same things also goes for oolong. Instead of torching it with boiling water, aim for between 185 and 195 degrees Fahrenheit. The delicate leaves will respond better to the gentler heat and the unique characteristics of the tea will be easier to taste and better on your palate.