Canadian Packaging

Making The Cut


May 25, 2010
by Canadian Packaging Staff

Product exits Loma’s IQ3 metal detector and is conveyed to the packing area.

Processing big blocks of cheese into millions of tiny slices, chunks and shreds day after day is a tasking enough way to make a living without having to worry about little bits of metal or other debris finding their way into the finished packaged product.

Fortunately for folks at the Alpine Slicing & Cheese Conversion in Monroe, Wis., the risk of metal contamination has become a thing of the past ever since the company discovered the inherent performance advantages of the cutting-edge IQ3 variable frequency metal-detection systems from Loma Systems, Inc.

“We take bulk cheese from different cheese plants and we convert it into a combined total of 78 different products and sizes, ranging from an eight-ounce chunk, wedge or package of slices to a five-pound deli piece,” explains Monroe plant manager Bill Stuart.

“All of these pieces run through our metal detector,” says Stuart, whose operation typically uses polyethylene-based film structures on a variety of packaging equipment—including vacuum, gas-flushing, and horizontal and vertical form/fill-seal machinery—to wrap the product after it passes through the metal detection stage.

“Before variable frequency came along,” Stuart recalls, “you’d have to set the metal detector at a compromise point that would work for all your products across the board.”

Historically, metal detectors were designed to operate on a single frequency, which was calibrated to specific product characteristics.

Despite the introduction of two- and three-frequency units expanding those capabilities somewhat in recent years, the tendency to deliver statistically compromised results had remained in place.

Loma’s IQ3 technology, on the other hand, takes things to a  higher level by offering users both state-of-the art sensitivity and stability, giving packagers with multi-product requirements superior accuracy and flexibility.

These capabilities are made possible by recent advances in case and coil geometry that prodcued a quantum leap in immunity from vibration, electrical interference and thermal shock—enabling increased stability and fewer “false positive” readings, according to Loma.

Additionally, improved sensitivity delivers an even greater capability to detect metal contaminants, as Stuart points out.

“The ability to detect small particles, accurately has really improved with the IQ3  system,” he states. “It’s just one more tool for us to meet our HACCP (Hazardous Analysis Critical Control Points) requirements,” Stuart says.

A package of Monterey Jack cheese slices passes through Loma’s IQ3 metal detector on its way to the packing station.

In operation, the IQ3 variable frequency metal detector analyzes various  “product affect” factors—temperature, moisture, salt content, speed, packaging material, etc.—to reviews a broad band of frequencies and to select the right one for the specific application within seconds.

This frequency selection basically removes operator error from the equation, according to Loma, while allowing a broad variety of products to be run through the same unit.   

Stuart says he also appreciates the fact that the IQ3 is built to withstand the harshest of operating environments.

“The units are also extremely user-friendly, making it very easy to set up for running a new product,” he adds.

“We haven’t had any problems with the machine or training our people on how to use it,” Stuart says, complimenting the system’s graphics-driven touchscreen interface that simplifies all the communication and operation issues.

Cheese slices are transported to the wrapping station.

Stuart says that the first IQ3 metal detector purchased by Alpine was outfitted with optional casters, so that it was wheeled to wherever it was needed at the plant.

But as the operation grew to house five separate production lines, the company purchased three more IQ3 metal detectors—with all of them installed in a fixed position on their respective lines.

Says Stuart: “More and more companies won’t do business with you if you don’t have metal detectors, but  Loma’s IQ3 makes us very comfortable and confident that we are always meeting our quality control objectives.”