As producers strive to keep up with regulation surrounding the Food Safety Modernization Act, inline metal detection, X-ray inspection and vision systems become even more important.
A quick look through the Food and Drug Administration recalls will show a number of products found to have potential safety problems, from possible foreign matter in whole wheat flour, to small metal shavings in apple coffee cakes, to small metal fragments in a brand’s gourmet cookies and plastic pieces in a bakery’s muffins and brownies.
“FSMA has created an increased level of focus in all areas pertaining to the safety of the products we consume and the individual ingredients that are combined to manufacture them,” Robert Rogers, food safety expert at Mettler Toledo, told Baking & Snack.
Automatic safety and inspection tools that complement or replace manual inspection can help food manufacturers ensure product safety from one end of the plant to the other. Inline safety and inspection systems can detect and prevent problems earlier in the production chain, kicking out rejects, lessening the chance of damage to equipment and ultimately saving time otherwise spent on backtracking.
Advances in technology
Inline systems aren’t new to the industry, but they have seen rapid advances in controls and technology over the last handful of years. Today’s systems can “learn” products on their own and eliminate noise and product effect, and some complete do away with manual training.
For example, Fortress Technology developed its Interceptor metal detector to use simultaneous multi-frequency operation in order to improve the systems’ sensitivity. It does this by procession multiple frequencies over a broad spectrum.
Product effect can cause false rejections because conductive elements like moisture, salt or iron alter the electromagnetic field of a metal detector, simulating the presence of metal when none exists, according to Heat and Control. The food processing, packaging and weighing equipment manufacturer combats this with its CEIA THS/MS21 technology, which differentiates between metal and product effect.
TNA North America, meanwhile, uses new technology for its Hyper-Detect 5 system to solve weaknesses caused by the physical shape of the metal detector’s inspection gateway. These systems are typically installed on snack packaging lines between the net-weighing scale and the bagger.
“We changed the geometry of how product passes form scale through the metal detector and into the bag,” says Mark Lozano, sales manager for TNA. “The coils’ ability to detect metals is weakest in the center of the detection zone. With the new design, the product does not flow through the center. Therefore, you get higher detection levels and better accuracy.”
While some food products and baked goods are packaged in plastic films or paperboard cartons that provide no interference to metal detectors, those packaged in foil pans or metalized films present a different problem, one requiring X-rays.
While slow inspection speeds in the past tended to work against use of X-ray technology, modern systems solve such limitations.
Meketic USA’s Midmeki mid-range unit operates efficiently at conveyor speeds nearing 6.5 feet per second, according to the company. The compact units have on-screen displays that pinpoint the exact location of the contaminants in the product. This helps operators take corrective action more quickly. All reject images are saved for later analysis and traceability, an important aspect of any inline safety management system.
Because X-rays provide an inside look at every product, they exceed human inspection capabilities. They can find broken cookies or cracked pizza crusts within packages and count objects to verify coverage or fill. This applies to all products that pass through the system.
“Samples measured manually can represent just a small fraction of the products made on the line, whereas the inline inspection system measures 100 percent of the products made and records statistics for each measurement every two minutes or for a period set by the user,” says Andrew McGhie, business manager for EyePro Systems USA. “The system generates reports based on shift, day, week and month, with date and time stamps, providing results for all products inspected.”
Laurie Gorton contributed to this report