Moisture and broken-tea content are the two parameters behind most bulk-tea disputes. Both are testable with simple equipment — here is how buyers verify them before and after shipment.
Moisture Test (target ≤ 6.5–7.0%)
- Laboratory method (reference): 5 g of tea, oven at 103±2°C for 4 hours (GB 5009.3); reweigh to 0.001 g. Moisture % = (loss / 5 g) × 100.
- Field check: squeeze a handful — leaf should snap and crumble, not bend. A quick moisture analyzer (halogen lamp) gives a reading in 10 minutes and tracks the lab within ±0.3%.
- Why it matters: tea above 7% molds in humid containers and on tropical routes; below ~4% it becomes brittle and breaks into dust during transport.
Broken Tea / Dust Test (target dust ≤ 1–1.5%)
- Sieve method: 100 g sample on a standard sieve set (e.g. 16/24/40 mesh); shake 100 strokes; weigh each fraction. The fraction below the dust sieve is the “powder” contract parameter.
- Particle consistency matters for tea-bag buyers: record the full distribution, not just dust — filling machines need uniform dosing. See tea-bag grade 41005.
Stem Content (target ≤ 2–5% by grade)
Sort 50 g by hand, separating woody stems; stems % = stem weight / 50 g × 100. Stems are the cheapest way a supplier cuts cost — make the limit contractual.
Writing It Into the Contract
- State method + limit: “moisture ≤ 6.5% (GB 5009.3), dust ≤ 1.5% (sieve test), stems ≤ 3%”.
- Per-lot COA + right of third-party inspection (SGS/Intertek) before loading.
- Sealed counter-sample as arbiter for sensory disputes.
Smileaf Tea issues COA with these parameters on every lot. Request specification sheets and samples →