How to Ferment Tea Leaves

Teas come in numerous forms and can be used for medicinal purposes, for energy or as a simple antioxidant-rich drink. Tea fermentation is the process in which tea leaves are allowed to dry and thereby undergo enzymatic oxidation. There are several degrees of fermentation, depending on what your tea needs are. Non-fermented/very lightly fermented teas retain much of their original flavor, such as green teas. Semi-fermented teas are those that undergo 10 to 80 percent fermentation. Fully fermented teas are completely dry, such as black teas. Post-fermented teas are those that are fermented, then have the process stopped before being fermented again. Fermenting tea can be accomplished manually or via proper machinery.

Things You'll Need

• Bamboo basket
• Wooden spoon
• Stove and oven
• Pan
• Tea roller

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Instructions

• 1

  Hand-pick tea leaves, which are harvested mainly as buds or young leaves, according to the website Taiwanese Tea Culture. Clamp the stem between your index finger and thumb and break off a leaf with a quick flick. Today many tea farmers attach a blade to their index fingers for quicker harvesting. Machines can also be used to pick the leaves, however Taiwanese Tea Culture notes that hand picking is still considered the optimal method for acquiring quality leaves. The leaf surface must remain intact for producing quality tea.

  Depending on variety of leaf, harvesting choices include "one bud one leaf", "one bud two leaves" and "one bud three leaves".

• 2

  Place picked leaves in a bamboo basket and leave them out in the sun to dry. Wilting the leaves with a hot air balloon machine is another option if such equipment is accessible to you. Whatever you choose, drying the leaves removes all moisture and subsequently causes oxidation, or fermentation. As the leaves dry, they will become both darker and softer.

• 3

  Relocate the basket of tea leaves indoors for "indoor wilting," according to Taiwanese Tea Culture. Gently stir the leaves with a wooden spoon or other stirring object, which will cause the leaves to rub against each and bruise their edges. This action, called waving the leaves, fills the tea leaves' cells with air, resulting in further fermentation. Waving can also be accomplished with proper machinery.

• 4

  Avoid excess fermentation, which causes the leaf edges to turn red. Too much forceful stirring causes the tea leaves to bloat and produces a bitter taste. Steam or pan-fry the leaves until the grassy smell has disappeared and you're left with a tea-like aroma. The stems and leaves are more flexible and slightly viscous at this point, leaving them susceptible to breakage.

• 5

  Place fired leaves in a tea roller and move the roller around, which causes the leaves to curl up and tighten. Be careful not to break or bend the leaves when placing them in the roller. Sap is released during this process and attaches itself to the leaves. The sap dissolves into the water to produce an aromatic tea when steeped. How much kneading your tea requires depends on the type of tea.

• 6

  Lie the kneaded leaves out on flat trays and place them in an oven or tea leaf dryer, if accessible. Dry the leaves, take them out to cool and place them in the machine to dry again until completely and fully dry. Store leaves for later use or roast and scent them for distribution.