Metal Detection: Multiscanning Turns Up Frequency for Food Industry

While no product test can replicate actual conditions, the more rigorous the test, the better. A testing process should specify performance requirements to provide confidence that the inspection solution will be suited to a specific application. Even for an advanced metal detector, such as one with multiscan capability, it’s important to follow a strict process to ensure each requirement is addressed. At a minimum, the testing should consider the following.

Product presentation and orientation. Results could be invalid if the product passes through the metal detector in the wrong way.

Production conditions. Temperature, pitch, and speed should match the actual production environment. Because temperature affects the electromagnetic signal given off by products, failing to factor in the unique signal of a hot versus cold product on a production line would lead to false rejects. Pitch should also be tested to understand the total amount of signal in the detector at any time and how many products might be detected at a time.

Placement of metal. Testing should be performed by placing metal in multiple locations on a package, including the center of the aperture, the weakest detection point because it is the farthest away from the metal detector coils. A thorough assessment should include tests on leading, trailing, absolute center, and sides to ensure metal is detected anywhere in the package.

Analysis of results. After testing is complete, a formal report should provide recommendations for each tested product, including recommended conveyor speed, frequencies, and setup parameters.

Finding the best metal detection solution is certainly easier than it once was. The most advanced instruments are now more reliable and versatile, bringing greater efficiency to manufacturers while requiring fewer trade-offs. It’s possible to have confidence, high throughput, and flexibility at the same time. Today, the high bar is multiscan technology, yet future advancements are inevitable. It may never be possible to make escapes 100 percent preventable, but today’s technology—supported by best practices—is already saving millions for manufacturers by avoiding costly recalls and, most importantly, ensuring food is safer for consumers.

Ries, the lead product manager for metal detection and X-ray inspection at Thermo Fisher Scientific, advises customers on specifying, installing, and using metal detection and X-ray systems to improve food safety and quality. Reach him at [email protected].