All tea was once a green leaf. After the harvesting of the tea leaves, they can be turned into black tea, oolong or green tea. It all depends on the manufacturing process, and process of oxidation.

Black Tea

Oxidized leaves
Freshly picked leaves (called “natural leaf” or “fresh leaf”) are transported to tea factories on the heads of labourers, truck, a transport rope, donkey or ox. In the factory the leaves are withered in order to become more pliable. In countries with drier climates, such as India, this can be a natural process. More humid countries like Sri Lanka (“Ceylon”) or Indonesia, this has to be a mechanical blowing of dry air. Leaves are spread on a rack and left to dry for up to 24 hours.

Partly dried leaves are then hand-rolled, so they release more of their essence oils: enzymes and juices. The way they are rolled will determine the quality and flavour of the brew.

Then they are sorted into different grades: size and state of the leaves (whole, broken).

Fermentation Of The Leaves

Fermentation oxidizes the leaves, and changes their chemistry: flavour, colour, body of the tea. The rolled leaves are placed on in a humid, temperature-controlled room for 1-3 hours. The temperature is of the utmost importance: if it is too hot the leaves will taste burnt, too cold will stop the fermentation process. Apart from temperature, the time this process continues is of great importance of the resulting tea quality.

This oxidation process gives the black tea its characteristic colour and flavour, and the skills of the tea master will determine the excellence or mediocrity of the resulting tea.

Firing the tea with blasts of hot dry air stops fermentation (oxidation) by destroying the bacteria and enzymes which drive the fermentation process, and stabilizes the leaves so they can be stored.

Black tea has about half the caffeine of coffee: 40-50 mg per 6-ounce cup.

(NOTE: oxidation is fermentation without yielding any alcohol)

Oolong Teas


A cross between black and green teas. The oxidation process is stopped after a 4-5 hours instead of a whole day, so the teas take on the subtle flavours of black teas while keeping the freshness of the green teas.

Oolong tea contain less caffeine than black teas.

Green Tea

Unfermented leaves

They are immediately heated in a large metal wok, or steamed, to break down the enzymes and keep the leaves from oxidizing. They too are rolled to release their flavours, and then dried to make the teas stable enough for storage. All of this is usually doen within a 24-hour time frame.

As it is processed less, green tea contains more of the beneficial properties than let’s say black teas.

It has half the caffeine of black teas. More about health benefits of green tea.

White Teas

Unoxidized leaves

The purest of teas. Hand-picked downy white buds of the Cmellia Sinensis bush are dried.

Pu-erh Tea

This is the only tea that is aged before processing. Its taste can improve with age, just like a good wine. Premium Pu’erh teas can be twenty to sixty years old. There is still very very little known about this mysterious tea, which is considered a medicinal tea, aiding digestion and believed to reduced cholesterol.