When used for machinery protection, the metal detector is installed directly before the machine to be protected. If, as in most cases in the food industry, consumer protection is the goal, several inspection points are useful. An inspection of raw material has the advantage that metal particles are separated before they are broken up into smaller pieces which might be harder to detect. Inspections at key control points during the production process are recommended to notice machinery failures (such as broken blades, metallic particles) in time.

Consequently, food products in their final stage after packaging are inspected once again with a metal detector to fully exclude contamination.

In order to obtain optimal product protection, an inspection of several key control points of the raw materials and a final inspection on the finished products are recommended.

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Detecting physical contamination in food

Physical contaminants, also referred to as foreign body contaminants, are physical objects that contaminate food. From farm to factory to fork, physical contaminants can enter food products at any stage in the food production lifecycle. For this reason, food quality control programs rely on inspection technology to detect and remove physical contaminants at many points throughout the manufacturing process.