Food Line Foreign Object Control
A foreign object control programme is judged at audit, not on the line. What matters is whether the detection limit is stated, whether rejected product provably left the line, and whether the record exists six months later.
Stage by stage, and what usually goes wrong at each
Hazard Review
Metal detection is bought by default even when the hazard analysis lists glass, stone or bone, which it will never see.
We ask what is in your hazard analysis first, and recommend X-ray instead of metal detection where the honest answer is X-ray.
Product Assessment
Wet, salty and frozen product generates a signal that masks real contamination, and datasheet sensitivity figures are empty-machine numbers.
We take your product description and give a realistic loaded expectation, then specify multi-frequency or phase-adapted detection where it is needed.
Position in the Line
Detection placed too early leaves contamination introduced downstream uncaught.
We site the check at the last point contamination can still be stopped, including pipeline detection for pumped product a belt machine never sees.
Aperture and Speed
An oversized aperture quietly destroys sensitivity, and a belt speed mismatch forces manual buffering.
Aperture is sized to the pack, not to the range, and belt speed is matched to the upstream line.
Rejection
An alarm-only detector leaves removal to an operator, and a rejected pack that re-enters the line undoes the whole control point.
Flap, pusher or air-blast rejection is chosen for the pack format, into a lockable key-access bin.
Records
Auditors ask who rejected what and when, which an alarm bell cannot answer.
We specify models logging image, timestamp and operator ID, and configure the log before go-live.
Changeover
Re-tuning at every product change varies by operator and eats line time.
Self-learning product memory is set up per product at commissioning, from 12 up to more than 100 settings.
Verification
A detector that drifts is only discovered at the next audit.
Test pieces are supplied with the machine and a verification interval is agreed against your food safety plan.
Food Line Foreign Object Control FAQ
How do we know whether we need metal detection or X-ray
Look at your hazard analysis. Metal only, a metal detector is cheaper and usually more sensitive to metal. Glass, stone, bone, hard plastic or foil packaging, you need X-ray.
Why is the real sensitivity worse than the datasheet
Published figures are measured on an empty machine. Product effect from moisture, salt and temperature reduces it. Any supplier quoting the empty-machine figure as your result is misleading you.
What makes a control point auditable
A stated detection limit, automatic rejection into a secured bin, and a log tying each reject to an image, a time and an operator.
Can we fit detection without replacing our conveyor
Yes. Search heads such as the VMS-4 and the separable rectangular head fit an existing belt without cutting it.
How often should we verify the detector
Against your own food safety plan. We supply the test pieces so the verification is meaningful rather than symbolic.
Start with the requirement, not the catalogue
Send what you are trying to achieve. We will work backwards to the equipment and tell you what it will and will not do.