Is X-Ray Inspection Or Metal Detection Right For You?

By Sam Lewis

A major thorn in the side of every food manufacturer or processor is the potential of foreign body contaminants entering food products, leaving the plant, and entering the market. There are many ways — including X-ray inspection systems and metal detectors — food makers battle the possibility of foreign body contamination. But, which one is right for you?

Both metal detection and X-ray inspection technology have long been safeguards in protecting food makers against foreign body contamination. However, as time passes, technology becomes more advanced — modern detection technology is fast, easy to use, cost-effective, reliable, and sensitive to very small contaminants — making the decision regarding which detection system to employ a very difficult one. When choosing to use X-ray inspection or metal detection in your food-making facility, consider the following.

Execution
It is well known that X-ray systems are capable of finding smaller contaminants than metal detection systems in a large array of products. Additionally, metal detectors have difficulty finding contaminants in wet and salty foods due to their conductive nature. However, that doesn’t mean X-ray is superior to metal detection, as X-ray systems have difficulty finding contaminants in dense, textured foods. Examining what types of foods you produce should be a major factor in deciding whether to use X-ray or metal detection.

Packaging
Your products’ packaging materials also can affect your detection system decision. Many food makers are exploring metallic packaging, including films, to boost shelf life and improve the product’s appeal to consumers. If your company is using this type of packaging, metal detection will not be able to see through the packaging barrier, and, consequently, any contaminants inside will be ignored. Your company’s current packaging and any future packaging changes should be considered when choosing a contaminant detection system.

Detection Point
Determining the point in your manufacturing, processing, or packaging line that presents the greatest chance of detecting contaminants also plays a role in which system to choose. Metal detectors can be placed at virtually any point in a food maker's lines. However, metal detectors work best in food products in small packages or bulk, conveyed foods. X-ray inspection systems work well with bigger packages and products and are often best utilized at the end of a production or packaging line.

Speed
Finding an inspection systems that is 100 percent reliable and runs at great speeds is almost always a challenge for food companies. If inspecting products at a high rate per hour is a major concern of your company, metal detection may be the best choice. Metal detection systems can utilize gravity-flow applications, making them completely functional at high speeds at any point in the line. X-ray inspection systems require slower speeds, consistent line speed, and more time to scan products and create images of the product and any contaminants within.

Other Applications And Added Value
Just like any other investment at your facility, you want your inspection technology to provide as many benefits as possible, as efficiently as possible, at the least cost. So, before investing in a particular inspection technology, it’s important to ask, “What else can this system do for me on top of finding contamination?” Since X-ray systems are able to see the contents within a container, they can determine if a product is missing a component (e.g., the steak or mashed potatoes in a three-course, microwaveable dinner). These systems are also capable of measuring a package’s shape and use product density data to assess approximate product weight.

Costs
Evaluating the immediate cost of the machine, as well as the total cost of owning the machine, should play a big role in your decision making process. Obviously, the immediate cost is the price of the equipment, but total cost of ownership — maintenance and repairs, parts, and equipment training, to name a few — is often ignored. X-ray systems carry a bigger initial price tag and total cost of ownership than metal detectors. However, they are also capable of finding a wider variety of contaminants than metal detectors, so this decision may hinge on not only initial cost, but the total cost of ownership.

Unfortunately, there is no “one-size-fits-all” product inspection solution. As mentioned throughout this article, many factors influence how well detection systems function. Your best bet in finding the ideal product inspection solution for your company is to evaluate the products you produce, how they are created and packaged, and ask your customers what type of inspection they expect your products to go through. If you face losing business for not having the right inspection system in place, I think investing in that type of equipment is obvious.