You may be surprised to learn that black tea, oolong, green tea and white tea all come from the same tea plant – the humble Camellia Sinensis. The difference in the colour, taste and caffeine level of say, a black tea versus a green tea is actually just down to the way the tea leaves are processed after they’ve been picked.
Black teas are made by picking the tea leaves then rolling and drying them. The leaves are slightly bruised which causes them to become ‘oxidised’, as the leaves start to ferment. This process turns the leaves a darker colour and causes the resulting brew to have that delicious, strong flavour and more of a caffeine kick than other teas.
To make a green tea, the leaves are fired or steamed. There is no ‘oxidisation’ stage involved so the leaves keep more of their natural green colour and retain more chlorophyll, which is why green tea has a grassy aroma. Because the tea is not oxidised it retains higher levels of antioxidants, tannins, vitamins and minerals and has a lower caffeine level than black tea. If you’re new to green tea, be sure to check our brew guide as boiling water will burn these more delicate leaves and the tea can become bitter if it’s not prepared correctly.
Oolong is somewhere in between a black tea and green tea. Think of it as the Rosé wine of the tea world! After the leaves are picked from the tea plant they undergo oxidisation, but the process is halted before the leaves become fully oxidised like a black tea. They get the best of both worlds, with a little of the grassy flavour of a green tea, but also some of the distinctive bold flavour of a black tea.
White teas are made from delicate, young tea leaves and can only be picked at certain times of the year when the tea plant forms new buds. White tea undergoes the least amount of processing with no oxidisation, rolling or steaming of the leaves involved. The buds are just picked and then dried, so it really is tea at its purest. It also contains the lowest levels of caffeine of any tea and is the highest in antioxidants with a myriad of health benefits.
Know your tea from your tea…
While we tend to call anything we brew with hot water a ‘tea’, technically speaking, only the products of the Camellia Sinesis plant are teas. Other plants and herbs that we commonly brew with hot water like mint, chamomile and rooibos are not actually ‘teas’ because, well, they don’t come from the tea plant! The correct term is an ‘infusion’ or a ’tisane’.