Everybody knows the importance of a well-rounded, balanced diet. Protein, vitamin D, omega-3, and iron – the list of crucial vitamins and nutrients goes on and on. Of course, not everything we consume is good for us, and over-indulgence always comes with its risks. One thing nobody should indulge in at all is a different kind of iron – the sharp, pointy metal kind that an unsuspecting consumer might choke on by accident along with a mouthful of overly hot chunky stew on “just one of those days”.
This is the kind of scenario that can spell the beginnings of a PR disaster for any company, big or small, and yet metal contamination happens more often than one might think. Metal represents the highest proportion of contaminants in food products, one of the reasons being that a significant amount of processing equipment is made up of metal.
The potential for contamination is huge. Everything from a chipped bowl to a worker’s loose button can represent a source of possible contamination. Without the right food grade metal detectors, testing protocols and safety training regulations in place, there is simply no avoiding the fact that food products that appear on grocery shelves will be contaminated.
What kinds of metal contaminants are out there?
Metal contaminants come in three main ‘flavors’: stainless steel, non-ferrous and ferrous.
Ferrous metals are the kind that typically contains iron, as well as small quantities of other types of elements or metals. They are magnetic and typically prone to corrosion. They represent a large proportion of the material used to make manufacturing equipment – think of mild steel, carbon steel, cast iron, wrought iron, etc. For instance, cast iron is used to make engine blocks, and cutting tools such as drill bits are often made of carbon steel. This is the easiest type of contaminant to detect.
Aluminum, copper, brass, silver and lead are examples of non-ferrous metals because they do not contain any iron at all. Nevertheless, whether it has iron in it or not, few people would willingly bite down on a piece of brass, which is why it’s important to have a contamination prevention plan in place, as well as the appropriate industrial metal detectors. Like ferrous metals, non-ferrous metals have their place in the manufacturing industry. For instance, copper is a good conductor of heat and electricity, which is why it is often found in pipe work and wiring. Silver is often used for soldering purposes. If they are present in the manufacturing environment, they can pose a contamination risk to food products.
Stainless steel can be found everywhere these days, from the food manufacturing industry to consumer appliances. This is because stainless steel possesses some attractive properties, such as corrosion resistance and a good deal of strength when compared to other metals like mild steel. However, it is less conductive than other metals and is not very magnetic. This means that even metal detectors for food industry use can have a difficult time alerting a user to its unwanted presence in a food product, which is why it is extremely important to have preventions plans in place, in addition to metal detectors.
The major food grade metal detectors
There are many kinds of metal detectors out there, but when it comes to detecting metal contaminants in the food manufacturing industry, the ‘balanced-coil’ and the ‘ferrous-in-foil’ detectors are by far the two most popular detectors.
Balanced-coil metal detectors are good general purpose options and can work on a range of different foods. They come in different configurations for different product types, so that everything from liquid or paste-like foods to packaged bread can be inspected in the most precise manner suiting the food product’s particular state.
Ferrous-in-foil metal detectors must be used for detecting ferrous metals in foods packed in foil. This is because balanced coil metal detectors cannot work accurately when foil packaging is in the way, whether it is a tray or a wrapper. Keep in mind that these metal detectors will only pick up on ferrous metal contaminants.
Preventing metal contamination in food
In order to prevent metal contamination in food products, it’s important to look beyond the technology. Industrial metal detectors will do their job if they are properly installed, maintained and calibrated, but food manufacturers need to go the extra step of properly instructing their staff on contamination prevention strategies. Documentation needs to be easily accessible at all times to employees who may have any questions or need to look up important information.
Employers must also set up the working environment to minimize contamination risks by identifying hazard risks and attempting to mitigate them. For instance, it would be prudent to schedule all maintenance to occur when possible during production off-hours. Having a maintenance worker welding broken equipment two feet away from a running production line is a quick way to contaminate food products. Workers should be trained to keep tabs on all their equipment, down to the tiniest drill bit, so that they always know what they have on them – and what they may have accidentally left behind.
Contamination testing procedures must also be implemented, and workers need to be trained in order to properly assess and respond to contamination situations. There must be documentation at all levels for traceability purposes; should a recall occur or a surprise inspection is undertaken, food manufacturers need to be able to provide solid evidence that they’ve gone out of their way to protect consumers from metal contamination.
Ultimately, it is the manufacturer’s role to ensure that its employees and consumers are protected from the hazards of metal contamination. It’s important to choose the right metal detectors for a given product to maximize contaminant detectability. With a combination of appropriate training, proper technology and a devotion to accountability, manufacturers can safely and effectively ensure the quality of their food products.