Over the years, the public has become increasingly concerned about what is in their foods. More recently, the focus has shifted to a concern over heavy metals. News articles about heavy metals have popped up more often, and many consumers are actively avoiding products with these contaminants.
With this in mind, producers need to be more cautious about ferrous and non-ferrous contaminants. Knowing what these are and how to eliminate them is a critical part of safe and compliant food production.
What Are Ferrous and Non-Ferrous Contaminants?
Iron is what separates ferrous and non-ferrous contaminants. Ferrous contaminants contain iron, while non-ferrous contaminants don’t.
For producers, a decision between metal contaminant detection methods is the biggest change this difference causes. In both cases, the contaminant comes from a metal, and a metal detector can find it. However, how this happens varies.
Some metal detectors only detect ferrous contaminants, while others only detect non-ferrous contaminants. Differences in metal detector frequencies cause this difference. Therefore, producers must think carefully when choosing an industrial metal detector.
Sources of Contamination
When comparing ferrous vs non-ferrous metal contamination, the source is usually quite different.
Ferrous Contaminants
Metals that make up ferrous contaminants include steel, carbon steel, alloy steel, cast iron, wrought iron, and more.
Sources of contamination for ferrous metals include:
- Machinery and equipment: Many elements of the food production line contain steel or iron to ensure their durability. However, if something goes wrong and part of the equipment chips while working with the food, bits of metal can make their way in, too.
- Processing environments: Alloy steel is common in construction settings, water pipes may contain cast iron, and nails and chains may have wrought iron. All of these may find their home in or around food processing buildings, giving them a chance to make their way into the food during that process.
- Raw materials: Sometimes, mistakes happen, and metals may make their way into the raw food materials before they even arrive at the processing facility. If undetected, they will stay with the food throughout the process.
Non-Ferrous Contaminants
Metals comprising non-ferrous contaminants include aluminum, copper, lead, zinc, tin, and others.
Sources of contamination for non-ferrous metals include:
- Packaging materials: Often, potential contaminants like tin foil or aluminum comprise food packaging materials. If the packaging sustains damage or if something goes wrong with the packaging process, the metals from these packages can make their way into the food. Canned and bottled goods often require additional steps as contamination affects these products differently.
- Utensils and tools: Non-ferrous metals compose many different utensils and tools that food processors use. If these chip or sustain damage in some way, the metal can end up in food.
- Environmental factors: These potential contaminant metals are often found naturally in the environment. If processors don’t sort them out, they will enter the food production process.
Impact of Ferrous and Non-Ferrous Contaminants on Food Safety
Health Risks of Ferrous Contaminants
The primary concern regarding ferrous contaminants is the risk of physical damage. If a shard of metal ends up in a food product, a consumer may ingest it. If this happens, it can cut someone’s mouth as they chew, or it could end up in the intestines, where it can lead to internal bleeding or other damage.
Health Risks of Non-Ferrous Contaminants
The scientifically demonstrated health risks of non-ferrous contaminants include vascular complications, blood lead, cancer, and more. Other issues, like lead poisoning, can build up over the years and lead to serious health problems, like reduced cognitive development in young children.
Regulatory Standards and Guidelines
Because of these risks, there are regulatory standards and guidelines in place that prohibit the inclusion of these materials. These vary and can come from a federal or local level. To help companies work within safe parameters, the FDA has published guidance relating to metal inclusion in foods.
Detection Methods for Ferrous Contaminants
Between ferrous and non-ferrous contaminants, ferrous contaminants are often easier to find and deal with. For these, detection and subsequent elimination tend to be more straightforward.
Magnetic Separation Techniques
Since many ferrous contaminants are sizable pieces of metal, magnetic separation techniques can sort them out. Running some foods through a mesh or sorter can eliminate many of the larger and more dangerous metals.
Metal Detection Systems
Ferrous contaminants are easier to find with industrial metal detectors because iron is easier for metal detectors to catch. So, with some basic knowledge of food industry metal detectors, companies can plan to detect ferrous metals.
Visual Inspection Methods
Visual inspection is another way to tackle larger pieces of metal directly. Once someone identifies a contaminant, they can remove it.
Humans can accomplish the process of visual inspection. However, it is most effective when paired with new food safety technologies like high-definition cameras. These can potentially spot and identify pieces of metals with greater accuracy.
Detection Methods for Non-Ferrous Contaminants
Between ferrous and non-ferrous contaminants, non-ferrous contaminants lead to more difficulty during impurity removal in manufacturing. These need specific frequencies for metal detectors to identify and, thus, have more advanced metal detector requirements. However, there are also additional ways of dealing with non-ferrous contaminants.
X-Ray Inspection Systems
X-ray systems go beyond what traditional metal detectors are capable of. They can identify a wide range of non-metallic materials and other contaminants that won’t show up in a traditional metal detector, like non-ferrous contaminants. Plus, they can look through metallic packaging to see if contamination has occurred within.
Because of this, many food manufacturers choose to use x-ray machines as a way to look out for food safety and metal contaminants. X-rays can even look for other sources of contamination, like plastic or glass.
Optical Sorting Technologies
Like with ferrous metals, processors can visually sort out some larger non-ferrous contaminants. Advanced optical sorting machines do this automatically. By integrating these into the production process, companies can add an additional point of quality control for foreign objects.
Electrostatic Separation Techniques
Traditional separation methods, like sieving, don’t always work with non-ferrous contaminants. Since these contaminants can be the same size as the food products they are with, they simply don’t separate in this fashion.
However, electrostatic separation presents a novel new way to tackle this issue. It charges the particles and then separates them in an external electric field.
Prevention and Control Measures
Preventing ferrous and non-ferrous contaminants from entering foods means taking the right steps.
- Good manufacturing practices (GMPs): Steps like following FDA guidelines and ensuring processors take proper safety measures will result in better manufacturing practices with fewer errors.
- Hazard analysis and critical control points (HACCP): Establishing multiple critical control points (CCPs) will provide intentional stages to catch and contain contaminants.
- Equipment maintenance and cleaning procedures: Properly maintaining and cleaning equipment lowers the chances that the equipment itself will contaminate the food.
Properly Handling Ferrous and Non-Ferrous Contaminants
For companies, preventing ferrous and non-ferrous contaminants from making their way into food products is an involved process. It starts at the very beginning and needs to continue through the entire process. One point of failure opens the door for contamination.
However, preventing these contaminants is possible. By taking the right steps and properly utilizing metal detectors, companies can detect and eliminate metallic contaminants and keep consumers safe.
Make sure you’re using detection equipment that meets your needs. Call TDI Packsys at 877-834-6750 for personalized assistance in choosing customized detection solutions.
