You avoid foreign bodies by making sure the whole spice is properly cleaned before grinding, then controlling the plant itself: sieves, magnets and metal detection on the line, and strict rules on packaging, clothing, glass and pests. Most foreign bodies in spice powder come in either with the raw material or from the factory.
Once a stone is ground into powder it cannot be picked out. Prevention has to happen before the mill.
Where foreign bodies come from
- Stones, mud and sand from fields and open drying yards.
- Plastic threads from woven PP bags, especially when bags are slashed open with a knife.
- Jute fibres and string from older packing.
- Hair from staff without proper head covering.
- Insects and insect fragments from poor storage.
- Metal from worn machinery, screens and maintenance work.
- Glass and hard plastic from lights, windows, gauges and tools.
Controls before grinding
- Machine cleaning with sieves, aspirators and de-stoners, and colour sorting where the spice allows. See machine-cleaned versus sortex-cleaned.
- Opening bags along the stitching rather than cutting through the woven fabric.
- Inspecting each raw material lot before it enters the line.
- Storing raw spice on pallets, covered and away from walls, with pest control in place.
Controls in the plant
- Hairnets, beard covers and dedicated clothing for everyone in production, visitors included.
- No jewellery, loose items or open food in production areas.
- A glass and hard plastic register, with shatter-proof light covers and regular checks.
- A check sieve after grinding, magnets on the line and a metal detector on the finished pack. Our guide to metal detection and sieving covers what good looks like.
- X-ray inspection where your customer requires it, since it can find some stone and glass that a metal detector cannot.
- Engineering controls: tools signed out and back, and line checks after any repair.
- A packing area that is enclosed and kept clean, with no open windows over product.
What to write into the contract
State that the product must be free from glass, metal, plastic, hair, insects and other extraneous matter. Add a limit for acid-insoluble ash, which mainly reflects sand and soil, as a measurable check on cleaning. Agree how complaints will be handled, with photos, the foreign body itself and the retained sample.
Ask the supplier to keep and share a foreign body complaint log. A plant that tracks each case and fixes the cause improves over time. See handling a quality claim if something does reach you.
How Creston & Co handles this
We check the cleaning line, packing hygiene and foreign body controls during our factory audit, and inspect the product before loading. If foreign bodies are a recurring problem with your current supplier, ask for a free sourcing review.