In everyday food processing, we often overlook the unsung "safety guard" of magnets. They exist in various forms throughout the production line, silently safeguarding food safety and quality from the moment raw materials enter the factory to the moment finished product leaves the factory. How do these seemingly simple magnetic devices become such an essential and crucial part of the food processing process? Let's explore the important role of magnetic technology in the modern food industry.

Where does metal contamination in food come from?

- Impurities in raw materials: Metal fragments may be mixed into crops during the planting and harvesting process.

- Equipment wear: Metal wear particles generated by processing machinery during operation.

- Human factors: Metal objects (such as buttons and jewelry) accidentally dropped by employees.

- Maintenance: Small parts such as screws and nuts that may be left behind during repairs and maintenance.

These contaminants range from bolts as large as 50 mm to wear debris as small as 30 µm, which can puncture packaging, cause cuts in consumers' mouths, or damage expensive subsequent equipment.

Magnetic Separation Technology: The Unsung Hero of the Food Industry

Magnetic separation technology utilizes high-intensity magnetic forces to effectively remove iron and other magnetic metal contaminants from food raw materials and production processes. Common magnetic separation equipment includes:

- Magnetic bars: Installed in feed ports and conveyor pipes to capture iron filings

- Magnetic screens: Used to filter metallic impurities from liquids and slurries

- Drawer magnetic separators: Remove fine metal contaminants from free-flowing dry products

- Magnetic separators: Used to screen and remove iron from recycled powders

Applications of Magnetic Technology in Various Food Industries

1. Grain Processing

In the processing of grains such as rice, flour, and cornmeal, strong magnetic bars are installed at the inlets of raw material cleaning equipment, mills, and packaging machines to effectively remove iron impurities from the raw materials.

This not only preserves the color and taste of the product but also extends the life of the equipment. For example, after installing strong magnetic bars in their production line, a large rice processing company reduced the amount of foreign matter in their product by 98%.

2. Edible Oil Production

In edible oil production, strong magnetic bars play a role throughout the entire process, from oil pressing to refining:

- During the pressing process, they prevent iron impurities from entering the oil pressing equipment.

- During the refining process, they further absorb iron impurities from the crude oil.

3. Baking and Confectionery

In the baking and confectionery industry, magnetic separators are used to inspect all incoming dry ingredients (such as flour and sugar) and liquid feeds (such as flavors, spices, and oils).

For example, Colonial Cookies of Canada has installed Pneumag magnetic separators and multiple fluid filters in its production line to protect its cookie manufacturing process from metal contamination.

4. Food Additive Production

The purity of food additives directly impacts food quality and safety. Strong magnetic rods ensure the purity of additive raw materials and prevent iron impurities from affecting the performance of food additives.

Magnetic Separation Technology and Food Safety Management Systems

Magnetic separation technology is a key component of the HACCP (Hazard Analysis and Critical Control Point) system. HACCP is an internationally recognized analytical system for identifying potential risks and implementing preventive measures to eliminate or reduce hazards.

A robust HACCP system with high-quality metal separation and detection offers many advantages:

- Monitoring raw materials from suppliers

- Preventing metal contaminants from entering the production process

- Promptly detecting machine wear or failure

- Control points that reduce unplanned maintenance and downtime

Many retailers today audit their suppliers' safety management systems for compliance with international standards, such as EU Regulation 852/2005 and ISO 22000. An effective magnetic separation system can help companies meet these regulatory requirements.

Key Considerations for Selecting and Maintaining Magnetic Separation Equipment

1. Raw Material Characteristics: Particle size, moisture content, and fluidity of the raw material will influence equipment selection.

2. Production Process: Continuous vs. batch production, and the degree of automation required.

3. Contamination Risk: The type and magnitude of potential metal contamination.

4. Cleaning Requirements: The ease of cleaning and sanitation of the equipment.

Regular inspection and maintenance of magnetic equipment is also crucial. This includes regular cleaning to remove adsorbed metal impurities, checking for weakening of the magnetic force, and ensuring proper installation.