What Is Green Tea. Why Drink Green Tea

What Is Green Tea, Anyway?

First things first: The word “tea” is only used correctly when it refers to leaves taken from the Camellia sinensis bush. And that means that herbal teas really aren’t tea – only green, black and oolong tea are the “real thing.” That said, the way the Camellia sinensis leaves are processed will determine which of these three choices the end product becomes.

To make black tea, the freshly picked tea leaves must undergo a process called oxidation. Oxidation occurs when an enzyme in the tea leaf called polyphenol oxidase is brought into contact with the air. To do this, the leaves are left in the sun for 18-24 hours to wither and dry; then they’re broken up to encourage further oxidation. Steaming, pan-firing or roasting the leaves stops the oxidation process, after which they are rolled, twisted and dried. Making oolong tea involves a similar process, although the leaves are withered for a shorter period, which produces a partially-oxidized leaf. But for green tea, the leaf isn’t withered or broken at all – in fact, just the opposite! The tea leaves are steamed almost immediately after picking in order to stop the oxidation process, after which they are rolled and dried.

The health benefits of the resulting tea will largely be determined by whether or not the tea leaf has been oxidized. That’s because the fresh tea leaf contains large amounts of catechins (pronounced “CAT-i-kins”), which are the powerful disease fighters and potent antioxidants that give green tea its health-enhancing abilities. But when exposed to air and polyphenol oxidase, the catechins change into completely different compounds called theaflavins and thearubigens. The theaflavins and thearubigens, which give black tea its distinctive taste, aroma and dark color, do have some health benefits, but not the same wide-ranging antioxidant and disease-fighting prowess seen in the catechins.

So in green tea manufacturing, it’s extremely important to rush the freshly picked leaves from the field to the manufacturing plant, being careful not to break or bruise them. There, the leaves are steamed or pan-fired immediately to inactivate the polyphenol oxidase. Afterwards, it’s safe to roll, twist, dry and package the leaves without worrying about obliterating the catechins. Yet even after the manufacturing process has been completed, green tea catechins can be destroyed if exposed to oxygen for too long. That’s why you should always keep your green tea in an air-tight container, even if it’s already in tea bag form. Remember: oxygen is the catechins’ worst enemy!