Metal Detector Upgrade Helps Cheesemaker Satisfy Growing Demand

Wet product effects can drown out signals that metal detectors are trying to detect—in particular, those caused by a stainless-steel contaminant. The Interceptor overcomes that tendency through software algorithms that distinguish between indicators specific to the product and those that flag anomalies. By singling out low-frequency signals, the Interceptor leaves the alert from stainless steel more readily identifiable in the higher-frequency range. The result of separating these two readings is that any genuine contamination from metal is not swamped by product effect.

False-positive rejects have also fallen since the systems were implemented, according to van Put. “Fortress metal detectors are really sensitive. This helps us to feel confident that the risks of contaminants are minimal, with less chance of a food safety issue,” he says. “Having the double readings within the Interceptor system also lowers the risk of false-positive rejects, which saves on food waste.”

Though Vepo Cheese products come in a variety of forms and packages, the Oudewater facility produces only shredded cheese in pillow packs. The plant produces several types of cheeses, however, and van Put says that the Fortress system makes changeovers quick and easy through the HMI software.

This is important, Schuurman notes, because each cheese has its own characteristics that could affect the sensitivity of the detector. “With the difference in product, they want to use programs as little as possible,” he adds. “A metal detector that helps them with this is a godsend.”

Automation efficiencies

Before the upgrade of the lines, Vepo Cheese was working with four different metal detector brands at the Oudewater facility, according to van Put. It was important to him and his team to have all seven metal detectors on the new lines be identical. It means fewer spare parts, easier maintainenance, and easier repairs. “When you know one system, you know them all. When you have a failure, it’s easy to find it because you have seven of the same systems,” van Put explains. “For the operator, it’s easy—when you’re standing, for example, at line 1 and the next day at line 5, it’s the same operation, the same look and feel.”

The automated reject system enables the cheese factory to isolate rejected packs without interrupting the production flow.Vepo CheeseThe ability to isolate rejected packs without interrupting the production flow was also crucial to Vepo. On previous inspection lines, the company did not have an automated reject system. If a contaminated pack was identified, the belt would stop, and an operator would have to intervene, remove the pack, and restart the inspection process. This interruption impacted productivity. 

More important, though, is the safety aspect of knowing that any packages with issues are guaranteed to be taken out of production, van Put notes. “The automated reject system gives us 100% control over production. There’s less human involvement, therefore less risk of human error,” he says. “This also lowers the risk of a metal contaminant slipping through the safety net.” 

Processing transparency was also important to the cheesemaker. Vepo’s previous inspection systems, coming from different manufacturers, did not work on a central network, van Put notes, so they were not able to share the data from test results. “All the people were writing down those results on paper,” he explains. “And when you have a lot of paper, it’s very difficult to make the root-cause analysis afterwards when you have a problem.”

On the new lines, each metal detector features Contact Reporter software. Data from each packaging line is collated in a universal collection system, enabling quality assurance and production managers to monitor processing and inspection performance from a centralized location. This automated record keeper developed by Fortress also helps the factory to keep track of and record data for rejects, tests, and process settings.

>>See how food processors are taking advantage of data capabilities in their inspection systems. Read "Smarter Food Safety Relies on More Data, Compute Power."

The installation, which went live in August 2019, took only half a day through careful planning with Jansen Controls, van Put comments. “We are extremely satisfied with the innovation and level of industry knowledge and support that Jansen and Fortress deliver between them,” he says. “The two teams understand exactly where we are coming from in terms of balancing product quality and enhancing operational productivity.”

>>Other content you might be interested in:

• Cheese Producer Welcomes Automation
• Sausage Maker Bridges the Gap Between Tradition and Technology With Metal Detectors