Sieving, Sorting, and Picking Out Huangpian: Before Maocha Becomes Tea

Sun-dried maocha (raw, unrefined tea) already looks like tea, but spread a handful on the table and you'll see long pieces and short ones, coarse and fine, mixed with old yellow leaves, thick stems, and now and then a hair or a sliver of bamboo. Between maocha and a handsome tea cake lies one more stage: refining.

What Is Refining?

Refining turns finished maocha into clean raw material of consistent grade. The usual refining steps for pu'er are:

1. Sieving: separating the tea by thickness and length with screens.
2. Winnowing: using air to blow away light flakes and dust, leaving the weightier leaves.
3. Picking: removing yellow leaves, coarse stems, and debris by hand or by machine.
4. Blending (depending on the product): mixing materials of different grades and origins in set proportions.

For ripe tea, refining happens after wet piling (wodui). The process is similar, but the clumps that form during piling also have to be broken up. See After the Pile.

Why Sieve?

Leaf size varies a lot within a single batch of maocha. If it isn't separated, the fine bits settle to the bottom of a cake during pressing while the coarse leaves stay on top, and the first few infusions will taste quite different from the later ones. Sieving does several jobs:

• Grading: separating tender buds and leaves from sturdier leaves to make products of different grades.
• Making "sa mian" possible: tender, good-looking leaf is set aside as the "face tea" on the surface of the cake, while sturdier leaf becomes the "inner tea."
• Removing fines: tea that's too broken is collected separately and can go into tea bags or other products.

Common machines are the round sieve and the shaking sieve: the round sieve sorts by thickness, the shaking sieve by length. The handmade method uses bamboo sieves, one layer after another.

What Gets Picked Out?

Picking is the most labor-intensive step of refining. The usual targets are:

• Huangpian (yellow leaves): older yellow leaves that won't roll into strands. See Huangpian: The Old Leaves That Get Picked Out.
• Thick stems and tea fruit: overly thick twigs, tea seeds, flower bases.
• Off-color leaves: scorched or reddened leaves caused by poor kill-green or drying.
• Non-tea debris: bamboo slivers, bits of grass, hair, small stones, and so on.

At processing stations and factories in Yunnan you'll often see a row of women seated at a long table with maocha spread in front of them, one hand spreading the leaf, the other picking. On many tea mountains it's a familiar sight after the harvest season. Large factories also use color sorters, which use image recognition to pick out yellow leaves and stems by their color.

Is Cleaner Always Better?

Not necessarily. It depends on what kind of tea you want to make.

A moderate amount of stem actually adds sweetness and body to the liquor, and many traditional recipes keep some stem on purpose. Yellow leaves, though picked out, make good tea in their own right. What really must go is debris and clearly defective leaf.

Refining and Grades

After refining, maocha is divided into grades. In the era of the state-owned tea factories, raw material was commonly labeled grade 1 through grade 10, with lower numbers meaning more tender leaf. These grades were also written into the recipe codes (maihao): in a four-digit code, the third digit traditionally indicates the grade of the main material. See How Recipe Codes Work. The national standard for loose ripe pu'er has 11 grades: special grade plus grades 1 through 10.

After Refining

Refined material can be packed directly as loose tea. Tea destined for compression goes on to weighing, steaming, and pressing; see Pressing Pu'er: Steaming, Stone Molds, Machine Presses, and Compression. Tea for blending is mixed according to its recipe; see Blending: The Art of the Recipe.

Reading Refinement in a Cake

When you pry open a cake, look at whether the leaves on the surface are even, whether yellow leaves are showing, how much broken leaf there is, and whether there's any debris. Carefully refined tea opens up clean and well layered, and the taste stays more consistent from one infusion to the next.

FAQ

What is refining? Sieving, winnowing, picking, and grading maocha into clean raw material of consistent specification.

Why sieve? To make leaf size and length consistent, which makes grading, surface layering, and pressing easier and keeps infusions more even.

What gets picked out? Yellow leaves, thick stems, tea fruit, scorched or reddened leaves, and debris like bamboo slivers and bits of grass.

Is a lot of stem a sign of bad tea? Not necessarily. A moderate amount of stem adds sweetness and body, and many recipes keep some on purpose.