Before you commit a container, you can judge 80% of green tea quality with three checks — dry leaf, liquor and leaf base — plus two contract parameters. Here is the method our QC uses on every lot.
1. Dry Leaf Judgment
- Twist integrity (条索): high grades show tight, thin, uniform rolls; loose, broad, ragged leaf means lower grade or poor rolling.
- Color: natural dark greyish-green is correct. A dull, brownish tint suggests old tea that has been re-baked to look fresh.
- Stems and dust: shake a handful — visible woody stems and fine dust at the bottom of the bag raise the grade question. Contract limits: dust ≤ 1–1.5%, stems ≤ 2–5% by grade.
- Dye test: rub a pinch of leaf on white paper; color transfer means artificial dye — reject immediately.
2. Liquor Judgment
Brew 3 g in 150 ml at 80–85°C for 3 minutes. High-grade green tea gives a bright, clear yellowish-green liquor. Dark, turbid liquor indicates over-fixation, old leaf or excess dust. The brightness should persist on the second infusion, not collapse.
3. Leaf Base (叶底) Judgment
Spread the brewed leaves: good lots show soft, even, greenish-yellow leaves with intact edges. Scorched patches, coarse dark old leaves or mushy uneven texture reveal sloppy processing or blended low-grade material.
4. The Two Numbers That Protect You
Moisture ≤ 6.5% and total ash ≤ 7.0% (GB/T 14456). Moisture above 7% predicts mold risk on ocean freight; abnormal ash signals contamination or added mineral matter. Both belong on the per-lot COA.
5. Season Check
Spring crop: more tips, higher aroma, sweeter cup. Summer: more stems, bitter. Autumn: thin liquor. Ask the supplier to declare crop season and match it against the dry-leaf tip ratio you see.
Put it into practice: request free grade-comparison samples from our sample desk and cup them side by side. Related: Green Tea Guide · test moisture & dust yourself