Aluminum is all around us, from the air we breathe to the food we eat. It comes from both natural sources like groundwater and artificial sources like food additives.
The list of products that contain aluminum is long: infant formula, cooking spices, deodorants, toothpaste, antacids, and immunizations. People can swallow aluminum, breathe it into their lungs, and absorb it through their skin.
While some exposure to aluminum is inevitable, there are some places where it shouldn’t be. Food manufacturers must take steps to avoid unwanted aluminum contaminants in their products, whether from industrial dust, package transfer, corrosion problems, or equipment defects.
Read on to learn more about how you can prevent aluminum contamination from compromising your operations.
What Is Aluminum?
Aluminum is a metal, like silver, iron, or lead. As the most abundant metal in the Earth’s crust, aluminum is present naturally in nearly all rocks and soils. It is also in water, air, and the human body.
When plants grow, they naturally absorb aluminum from the soil and water. That’s why low amounts of the metal show up in foods like mushrooms, spinach, radishes, lettuce, and some herbs. You can also find it in tea, dairy, cocoa, soy, and prepared foods containing grains such as bread, rice, cakes, and pastries.
Beyond the naturally occurring amounts, many industries add aluminum during the manufacturing of foods, drinks, and cosmetics. Small amounts of aluminum can improve texture and taste, help with emulsification, increase heat stability, and produce brighter colors.
The finished aluminum product as we know it comes from mining its raw material, bauxite. After processing, the lightweight metal has a host of applications, including cookware, beverage cans, food packaging, factory equipment, and building materials.
Sources of Aluminum Contamination
While aluminum is a common additive in small quantities, larger amounts of this metal can contaminate food, water, soil, and air in a variety of ways, including the following:
- Natural Sources: Aluminum can leach into groundwater supplies naturally from sources like soil and rock, rain, and dust that settles on surface water.
- Human Activities: Mining operations, coal-fired power plants, and even water purification systems can release aluminum into the environment.
- Manufacturing Processes: Pieces of metal, including aluminum, can contaminate products during food processing and packaging operations. For example, fragments of equipment can fall off, aluminum dust can settle onto ingredients, and pieces of foil can find their way into the food.
- Food Preparation and Packaging: Certain types of cookware (like uncoated pots or baking trays) and packaging materials (like foil and cartons) that contain aluminum can transfer small amounts of metal into food products.
- Materials Degradation: Because many consumer goods contain aluminum, the metal can leach into soil and groundwater supplies from landfills or other places where garbage is left to degrade.
How Does Aluminum Become a Problem?
Current research indicates that exposure to low levels of aluminum is unlikely to harm your health. The human body processes aluminum through the kidneys and excretes it through urine. Additionally, aluminum has low absorption in the intestinal tract. The evidence so far does not suggest that the metal bioaccumulates in humans (builds up in the body) or causes cancer.
In high doses, however, aluminum may be toxic. Acute high-level exposure can result in nausea, vomiting, diarrhea, and ulcers of the mouth. Most often, aluminum toxicity occurs when people inhale it as aluminum dust or fumes in industrial settings or eat it, such as by overconsuming aluminum-containing antacids or food products.
Scientists have also questioned whether there is a link between aluminum and neurodegenerative diseases like Parkinson’s, Alzheimer’s, and Lou Gehrig’s disease (ALS).
Furthermore, aluminum can pose a problem as a foreign body in food products. Like any other foreign material, pieces of aluminum can cause people to choke or suffer injury to their mouth, throat, stomach, or intestines.
Standards for Aluminum in Food Processing
For the average person, food is the biggest contributor to aluminum intake. Although dietary aluminum consumption alone is not likely to cause problems for healthy individuals, chronic exposure from a variety of sources, including aluminum contaminants from food processing, may lead to exposure above tolerable levels.
Government agencies have set standards for safe amounts of aluminum and developed regulations to prevent dangerous levels of aluminum contaminants. The U.S. Food and Drug Administration (FDA) allows the use of aluminum salts as “generally recognized as safe” additives to foods and beverages.
However, facilities should follow good manufacturing processes and quality control inspections to prevent contamination. According to the U.S. Department of Agriculture (USDA), these include taking measures to prevent the accidental inclusion of metal or other extraneous materials in food.
In addition, manufacturers must design, construct, and use equipment in a way that avoids adulterating food with metal fragments, contaminated water, or any other contaminants.
Aluminum Detection and Analysis
In addition to potentially harming consumers, metal contamination during manufacturing can damage machines and stop production. For these reasons, industries employ a variety of detection methods and machines to prevent aluminum contamination.
Metal Detectors
Metal detectors use electromagnetic fields to discover metallic items, including aluminum contaminants. As a piece of metal moves through the detector, it disturbs the field. The signal then registers the presence of metal. Most manufacturers use standard food metal detectors to inspect packaged food products.
Due to aluminum’s high conductivity, food-grade metal detectors can detect its presence at much smaller sizes than other metals. However, metal detectors are not ideal for products that have metal containers or inserts.
X-Ray Machines
Instead of electromagnetic fields, x-ray inspection systems use density differences between the product and foreign bodies. This allows them to detect not only metal but also common contaminants like glass, stone, rubber, plastic, and bone.
X-ray machines are also ideal for detecting contaminants in products with metallic packaging that cannot be accurately inspected with a metal detector. On the flip side, because aluminum has a low density, it may not register on standard x-ray machines at the same small sizes as a food-grade metal detector would. By using Dual-Energy x-ray technology, this detection can be significantly improved to match the performance of metal detectors.
Control Systems
Modern control systems use software, algorithms, and artificial intelligence (AI) to analyze the results of inspection machines. This can help distinguish aluminum from the products around it during the quality control process, avoid triggering false alarms, and reliably identify metallic contaminants.
Aluminum Detection Solutions for Your Facility
Different inspection machines and methods are better for different food products and packaging types. For example, products with high fat, salt, or moisture content can impact detection systems. Similarly, packaged products need a different kind of inspection process than loose liquids do. Finding the right system is essential to accurate aluminum detection.
When evaluating inspection systems, consider what kinds of products you handle, whether you need to inspect packaged or unpackaged goods, and which of your manufacturing steps are most vulnerable to aluminum contaminants. Your budget, required sensitivity levels, and the industry in which you operate will also impact which machines and methods make the most sense for your application.
The best way to determine which x-ray system or metal detector is best for you is to contact TDI Packsys for a consultation. We offer free, no-obligation validation testing, in which we test your exact product on several systems using certified test cards or foreign material samples you provide. Our test will conclude with a formal report on the capabilities and expected performance of each type of technology. For more information, call us at (877) 834-6750.
