How To Choose a Food Metal Detector for Your Company

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metal detector for food industry

If you’re a food manufacturer, the last thing you want is for a customer to complain about biting down on metal chunks while trying to enjoy their dinner. Metal has no place in food; if it ends up where it shouldn’t, you could find yourself dealing with product recalls and costly lawsuits.

You need to buy a food metal detector that’s reliable and easy to maintain, but which should you purchase? Below, learn how to choose a food metal detector for your production line.

Determine Your Needs and Application

Before spending money on a metal detector, consider what you will use it for. Do you want to detect metal in food, machinery, or both?

Metal detectors have varying degrees of sensitivity. You may need a less sensitive detector near the front of the production line where you’re concerned about loose metal damaging machinery. Closer to the end of the line, where food is packaged, you’ll need a detector capable of finding metal with a higher sensitivity.

What Type of Food Products Will You Be Processing?

The type of food products your company processes plays an important role in helping you choose a food metal detector. For instance, a metal detector suitable for a sugar packing plant may not be appropriate for a meat production line. For the former, you’d need a metal detector capable of finding contaminants in granules and fine powders.

Does your plant process wet or dry foods? It’s easier to find metal in dry products than in wet ones. If you process orange juice or bottled water, you’ll need to buy a metal detector capable of picking up contaminants in liquids.

Foil-packed products require special consideration. The best option is to send the food through metal detection before packaging. If this isn’t possible, you’ll have to buy a ferrous-in-foil detector.

What Types of Metal Contaminants Can Food Metal Detectors Detect?

processing of ferrous and non ferrous metals in food factory

Industrial metal detectors are nothing like the low-powered models used by hobbyists. Conveyorized metal detectors find ferrous and non-ferrous metals, as well as metals that are difficult to detect, such as stainless steel.


Ferrous metals are the easiest type of metal to detect. This is because they contain iron and are typically magnetic. A good metal detector can easily find even a very tiny amount of ferrous metal in food.


Non-ferrous metals are harder to detect because they don’t have magnetic properties. These metals contain elements such as zinc, aluminum, and nickel. You’ll need a bigger sample size to find non-ferrous metal with your detector.

Stainless Steel

Stainless steel is the hardest type of metal to detect because it is a poor conductor and is usually non-magnetic. It becomes even harder to locate stainless steel in wet products or foods with a high salt content.

Assess Sensitivity Requirements

How sensitive must your metal detector be? You want a detector capable of picking up on contaminants while minimizing false rejects (this happens when the equipment flags something as metal when it’s not).

False rejects waste good product, slow down the production line, and put a dent in your company’s profits.

Factors affecting sensitivity include your packaging environment, product speed, operating frequency, and aperture size. One common way to boost your detector’s sensitivity is to reduce the size of the aperture. You may also consider a multi-lane system, which can slash false rejects by up to 75%.

What Size of Metal Contaminants Do You Need to Detect?

When selecting a metal detector, there is no one-size-fits-all solution for every production line. The detector you choose should be capable of detecting a specific size of metal contaminants. If you choose a level of sensitivity that can’t detect the size of contaminants you’re looking for, metal could get into your products.

To avoid this, consider the aperture size versus the product size you must inspect. The closer the product can get to the wall of the detector, the higher the sensitivity will be. If the aperture is too large compared to the product, there’s a higher chance of false rejections.

Verify Regulatory Compliance and Certifications

combined wooden block that form check icon

Make sure to purchase a metal detector compliant with the required regulations and certifications. We explain some of these below to help you know how to choose a food metal detector.


HACCP stands for hazard analysis and critical control points. Your metal detector should comply with its seven principles, which are as follows:

  1. Conduct a hazard analysis
  2. Identify critical control points
  3. Establish critical limits
  4. Establish monitoring procedures
  5. Establish corrective actions
  6. Establish verification procedures
  7. Establish record-keeping procedures

The detector should also comply with good manufacturing practice (GMP). GMP is a system that ensures you produce goods according to strict quality standards.

FDA Approval

The Food and Drug Administration (FDA) began regulating metal contaminants in food more than 50 years ago. To comply with FDA standards, manufacturers must try to limit the number of metals, plastics, and other contaminants in their food products.

FDA regulations prohibit metal fragments between 0.3 inches and one inch in size. Technically, metal pieces smaller than 0.3 inches are permitted, but that doesn’t mean you should allow them in your products. Tiny metal pieces can seriously harm babies, the elderly, and other at-risk people.

What Maintenance and Support Considerations Are Important When Selecting a Food Metal Detector?

When buying a food metal detector, you must think about support and maintenance. Factors to consider include the following:

  • How easy will it be to clean the metal detector, and does it have the appropriate washdown protection rating? For instance, if you require high-pressure and high-temperature water to clean your equipment, you’ll need a detector with an IP69K rating. On the other hand, if you use low-pressure, low-temperature cleaning methods, you can get by with an IP65 rating.
  • How simple or complicated is it to integrate the metal detector with your existing equipment?
  • What will your maintenance schedule look like? Maintenance is critical to help prevent breakdowns and contamination accidents.
  • What is the detector’s product effect?
  • How user friendly is the machine? Can you easily train workers to use it?
  • Does the machine include automatic performance verification? This feature quickly alerts operators to a potential problem, reducing the time contaminants may go undetected.
  • Is the supplier reliable? How quickly can they send support if something goes wrong?

What Are the Initial Investment Costs Associated With a Food Metal Detector?

Food metal detector costs can vary widely. You could pay about $15,000 for a basic model or over $80,000 for a more advanced detector. You can lower the cost by opting for a used model, but be aware that such detectors may not come with any warranty or support.

The upfront price of the machine isn’t the only cost to consider when choosing a food metal detector. You’ll also have to consider how much it will cost to run, clean, and maintain the detector. If you must shut down the product line for maintenance and repairs, you’ll have to account for lost production time as well.

Now that you’ve learned how to choose a food metal detector, contact TDI Packsys at (877) 834-6750 to learn more about our metal detection options.

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