USDA’s Food Safety and Inspection Service has developed a guideline to help meat and poultry establishments develop a written program to respond to complaints about foreign matter consumers find in meat and poultry products they purchase. The guideline outlines best practices companies can use to respond to these complaints.

But instead of knowing how to respond to complaints, isn’t it better for processors to take steps during processing to detect foreign material before it ever gets to consumers?

There are basically two types of systems that can be used in detection technology, particularly if the hunt is on for foreign material contamination in meat and poultry products, says Glenn Holliday, product manager, inspection, for Marel North America, based in Lenexa, Kansas. Marel is headquartered in Iceland.

One of them is X-ray technology, which is very good at finding metal, porcelain, glass and bone in meat and poultry products, he says. Metal detectors are another highly used detection technology, though X-ray technology is becoming more prevalent.

“We at Marel are always looking to improve. There is new technology that we’re looking into for future use with X-ray technology or by itself.”

Holliday points to problems in poultry and meat slaughtering and processing that lend themselves to soft foreign material contamination. “In processing, the processors are often buying combos of meat surrounded by plastic liners,” he says. “People are using box cutters – the cardboard and the plastic can get ripped off and end up in the meat.”

He also notes limitations in what inspection technology can do. “We never say X-rays are 100 percent effective. We make no claims about finding plastic or cardboard.” So plastic is still found largely through visual inspection. “But what X-rays can do is find bone.”

Marel came out with its first X-ray machines for poultry in 2006, which are used largely to find bone contamination. “We’ve been the poultry standard for fresh deboning detection ever since,” he says, with 600 machines specializing in bone detection in the poultry industry in North America.

While some people think automation can be blamed for more foreign material contamination in the industry, Holliday disagrees. “There have been automated lines for the last 20 years. When you had lines of people wearing chain link gowns and gloves, I think more came from them than automated machines.”

Early detection

Jeff Ray, Marel’s marketing manager in North America, points out that a top priority for inspection and detection technology is to find contaminants as early in the meat or poultry process as possible.

The company also offers product control software, enabling processors to tell what was tested for foreign material contaminants after the products are packed off into combos or boxes. This can limit recalls because processors know what was discovered. It creates an “electronic trail,” indicating where it came in, and where it is now.

Advanced Detection Systems metal detectors are sensitive to ferrous and non-ferrous metals.Advanced Detection Systems, based in Milwaukee, manufactures metal detection equipment for the food industry, including for meat and poultry, explains Dave Smith, sales manager for the company.

“Our products – the metal detectors – are sensitive to ferrous, non-ferrous and stainless-steel metals,” he says. Ferrous metals are magnetic and easiest to detect. Non-ferrous metals, like copper, aluminum, and brass, are highly conductive non-magnetic metals. “High quality 300 series stainless steels are the most difficult to detect, due to poor electrically conductive qualities and low magnetic permeability.”

Metal detection works because all metals are either magnetically conductive or electrically conductive or both. When they enter the metal detector, they create a detectable disturbance or signal. Modern metal detectors operate on the balanced coil, full loop system that allows detection of the signal from the metal.

Data logging is a very important part of metal detector use. “Metal detector data logging is the internal constant collection of metal detector events that are downloadable from the metal detector via USB cable or thumb drive,” Smith explains. “It’s important to the meat and poultry industry because logged metal detector events, such as metal detections, product settings and product setting changes are date and time-stamped. This downloadable record which is easily collected documents proper metal detector usage,” he notes.

Data logging is very important because it documents proper usage adding value to the investment in metal detection when its usage comes under scrutiny by internal food safety and management systems, like HACCP as well as customer audits and regulatory audits, from FDA and USDA, Smith says.

Smith also points to current metal detector trends in the industry. “In addition to documentation via data logging, there are recent developments in the use of multiple, simultaneous frequencies in highly conductive product applications.”

Addressing challenges

“Fresh, seasoned meat is a tough application because the conductive product effect of the meat interferes with the metal detector’s ability to detect metal contaminants,” Smith says. “The use of simultaneous, multiple frequencies has resulted in improved metal detection levels in highly conductive products,” he says.

“The technology in finding foreign matter in food products, including meat and poultry products, certainly has advanced, far ahead of what was being done years ago,” says Michael Ahern, Eastern Sales Manager for Anritsu Infivis Inc., a detection technology company based in Elk Grove Village, Illinois, that makes both metal detectors and X-ray equipment.

Metal detection research and development is enabling equipment to detect contaminants that are smaller and lower density than ever before.“In fact, everyone is trying to eliminate the smallest pieces of foreign matter. Detectors are getting better at finding the matter and finding smaller things. That’s the major trend in detector technology.”

He compares advances in inspector and detector technology to advances in iPhones over the years, where phone cameras can now take photos practically in the dark. “Of course, the technology isn’t the same, but you can see the advances being made in both types of technology,” Ahern says. “The detection of smaller matter at high resolution is a major trend with a simultaneous reduction in false rejects.”

In finding metal, metal detectors can’t find matter as small as X-ray technology. Metal detectors, for example, can find ferrous material as small as 1.5 mm and non-ferrous and stainless steel as small as 2.5 mm. “Today, X-ray technology in a similar-sized product can get below 0.8 mm, find smaller matter than that,” Ahern explains. “That was a huge advancement.”

While traditional X-ray technology uses single energy, there is now new dual energy X-ray technology. This is very helpful in finding bone in poultry, a big target. “The high energy absorbs muscle, fat and bone,” Ahern points out. “But the low energy part of the dual energy absorbs more calcium. It’s a good way to get bone out. That’s a huge advancement, to find bone in poultry,” he says. “And what’s coming down in research and development will enable us to find smaller and more low-density contaminants.”