The most common quality issues with Indian herbs are wrong or mixed species, soil and sand, high moisture, high microbial counts, pesticide residues, heavy metals, pyrrolizidine alkaloids and ethylene oxide residues. Colour and aroma loss and mixed plant parts are frequent complaints too.
Most can be avoided with a clear spec, a supplier who processes in their own plant, identity testing and testing every lot before it ships.
The main problems
- Identity: a look-alike species or a cheaper plant mixed in, especially in powders.
- Wrong plant part: leaf or stem mixed into root powders, such as with ashwagandha.
- Soil and sand: high total ash and acid-insoluble ash, common in roots and ground leaves.
- Moisture: herbs dried poorly or packed damp, leading to mould and caking.
- Microbes: high plate counts, yeast and mould, or Salmonella.
- Pesticide residues above the importing country's limits.
- Heavy metals, linked to soil, water and processing equipment.
- Pyrrolizidine alkaloids from weeds harvested with the crop.
- ETO residues from fumigation, which fail in the EU at trace levels.
- Colour and aroma loss from sun drying, heat or old stock.
How to prevent them
- Write a spec with botanical name, plant part, ash, moisture, microbial, residue, metal and PA limits. See writing an agri product specification.
- Buy from processors who clean, cut and mill in-house, not from unknown stock.
- Test identity on every lot with methods such as HPTLC, microscopy and macroscopic checks. See botanical identity testing.
- State "no ETO treatment" and test for ethylene oxide and 2-chloroethanol for EU and UK shipments.
- Require steam sterilisation where your customer needs low microbial counts.
- Test approval samples and each pre-shipment lot at an accredited lab.
- Keep a sealed reference sample and compare each lot with it.
Why problems appear after the first order
Many buyers get a good sample and a good first container, then quality slips. The supplier may change collection areas, buy in from a trader, or skip cleaning steps once trust is built. Our article on why quality drops after the first container explains the pattern.
The fix is steady testing on every lot, not only the first. Tie payment release to passing results where you can.
When a lot fails
Keep the failed result, the lab report and photos. Check whether the failure is in the sample only or across the lot by testing more bags. Agree in the contract in advance who pays for re-testing, replacement or return.
Some failures can be fixed, such as re-cleaning for foreign matter or re-sterilising for microbes. Others, such as ETO, PAs or heavy metals, usually cannot.
How we help
We audit herb processors, write the spec with you, test identity and contaminants at NABL-accredited labs, and inspect every lot before loading. If a problem slips through, we help you build and pursue the claim. Ask for a free sourcing review.