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Metal detector keeps sauce contaminant-free

Food Service Specialties (FSS) of Red Wing, Minnesota, processes and packages private-label tomato and dairy-based sauces to an ever-expanding customer base made up of restaurants, retailers and food manufacturers across the country. The sauces produced at its facility—among them pizza, marinara, spaghetti and barbeque—are prized by those customers who need to protect their individual recipes and maintain a high degree of sauce consistency from location to location and batch to batch. The sauce program at FSS also allows its clientele to eliminate unnecessary equipment, reduce the storage of raw ingredients, and save on disposal costs.

Naturally, customers rely on FSS for the most stringent production standards to protect their signature recipes, ensuring the finished sauce is free of any contaminants before leaving the facility. An important part of the company’s quality program has always been metal detection of the sauces to check for contamination such as ferrous, nonferrous and stainless steel metal.

“The metal detector is a critical step in our sauce processing because our customers demand an absolutely contaminant-free product,” says Rod Oberg, assistant plant manager at FSS.

When the company decided to switch to a newer, more updated metal detector, its requirements for a replacement were faster setup and processing, minimal training, and more robust reporting features. It chose the Eriez Xtreme® Liquid Line metal detector, which now inspects 80,000 lb of different FSS sauces for contamination on a daily basis.

‘Xtreme’ detection

FSS started out in 1985 by fulfilling a customer’s request to match and produce a unique pizza sauce. That initial foray into the restaurant industry helped FSS continue to attract new customers. By 1998, the company had outgrown its plant in Columbus, Wisconsin, and relocated to a 45,000-sq-ft facility across the border in Red Wing. About a decade later, the company added another 34,000-sq ft to its production floor.

“Our manufacturing plant is completely dedicated to private-label production,” says Oberg. “The success of our business has come from our ability to create customers’ unique sauces in our facility.”

The batch sizes of private-label products vary by customer, but the smallest batch produced at the facility is 9,000 lb (approximately 1,100 gal). No matter the batch size, checking for contaminants in a product like tomato sauce is vital, Oberg explains. “You are dealing with a field-to-fork product, so there are multiple ways for contamination to occur, especially during the slicing process, where small bits of metal can come off tomato slicers,” he says. “Metal can also make its way into the tomatoes while they are trucked to the plant.”

In evaluating metal detectors, Oberg met with Eriez technicians and Sales Engineer Larry Wamstad of Dynequip, Inc. at Eriez’s field sales office in St. Paul, Minnesota. Wamstad recommended the Xtreme Liquid Line, designed for liquids, pastes, slurries, or other viscous products where high-sensitivity metal detection is required.

Notes Eriez, the Xtreme’s greater sensitivity is enabled through the machine’s multiple frequency range and vibration immunity. According to Oberg, while most metal detectors can detect contaminants down to 4 mm, Eriez was able to program the Xtreme to get “consistently good results” at less than 2 mm. The system is also programmed to detect metal in a range of product viscosities, from a pure sauce to one that is thicker in concentration, with such as a sauce with chunky ingredients.

The Xtreme features a large, easy-to-use color display, a dedicated reject and event log, a verification program, and configurable inputs and outputs that enable easy installation. One notable innovation of the machine, Oberg shares, is the Smart X7 Link, which allows Eriez service technicians to troubleshoot remotely via the internet. It also enables FSS to view the Xtreme through its intranet.

Specification and startup of the metal detector at FSS was seamless. Says Oberg, “We did not require a lot of formal training on the metal detector. The Eriez staff asked questions about our customers and the type of sauces we wanted to monitor. Then they came back with the properly configured metal detector and training to fit our needs. It was basically plug and play after that.”

Rooting out a metal menace

During sauce production, after the product is processed, it passes through the Xtreme Liquid Line before being packaged into jars or bulk containers.

“It’s a straightforward system to operate,” says Oberg. “We process about 80 pounds per minute through the metal detector—or about 10,000 pounds every two hours and 20 minutes—running two shifts. Every sauce we make gets inspected for the slightest bit of metal contamination before final packaging.”

When metal is detected in the liquid product flow, a reject signal is channeled to an output relay. The relay then activates a reject valve that diverts the contaminated portion of sauce into a different container, which is then disposed of.

Wash down of the machine is rarely needed, Oberg explains, since FSS uses it mostly for tomato sauces. “When we do, it’s a low-level wash down, and we place a cover on the display to avoid damage or any unintended activation of the touchscreen,” he says.

At press time, FSS was preparing for the installation of a second Eriez Xtreme Liquid Line metal detector.