How to Avoid Mineral Oil Contamination in Food Processing

Dr. Holger Streetz, Banthan AG

Lubricants are vital to a piece of industrial equipment's overall lifespan. The main task is reducing the amount of heat produced by friction and abrasion. However, innovative lubricants are able to do much more.

Equipment longevity is essential for production growth, and as food processing has transformed into a high-volume industry, facility managers and processors need equipment and machinery to function at its most efficient level. Therefore, lubricants should be an essential part in the plant manager’s strategy.

MOSH / MOAH 101

From a chemical point of view, mineral oils are complex mixtures, the majority of which are saturated mineral oil hydrocarbons (mineral oil saturated hydrocarbons or MOSH,) and mostly alkylated aromatic petroleum hydrocarbons (mineral oil aromatic hydrocarbons or MOAH). MOAH are suspected of being carcinogenic, which is why their content in food according to the ALARA principle (as low as reasonably achievable) should be minimized.

There are many direct and indirect sources of MOSH / MOAH. Food additives such as release agents, coatings, glosses and anti-dusters are applied directly on the product. Other sources such as dressings and packaging materials hold the products and get in direct contact with the product as well.

Packaging materials (recycled paper, printing inks and jute bags) can be contaminated with mineral oil or, as in the case of ink, be part of the material. Dressings are often made from mineral oil-containing corrugated board. Gases and lubricants are used in the production process and therefore are indirect contamination risks. Compressed air can contain oil from the compressor, whereas lubricants are used in harvesting and processing equipment.

To exclude as many sources as possible, lubricants in the feed and food industry need to be H1-certified food-grade greases and oils. The most common legal basis for minimizing the lubricant quantities is FDA 21 CFR 178.3570, according to which the lowest amount of lubricant must be used to accomplish the desired technical effect on the equipment.

Lubricants in Food Processing

The customer’s mindset is of great importance when considering a change to food-grade lubricants. The experiences from the 1980s still seem to be very vivid, when using food-grade lubricants resulted in decreased performance and increased costs. However, when switching to premium-quality food-grade lubricants, the opposite can be found. Modern food-grade lubricants increase the overall equipment effectiveness while reducing the risk of product contamination.

The added value a producer can gain by using high-performance food-grade lubricants should be a primary focus. H1-compliant lubricants have already gained wider acceptance. However, they are still not universally adopted in all industry segments, regions or safety-critical operations. There are misconceptions on the cost competitiveness and potential advantages over conventional lubricants, which can partially be explained with the need to raise the bar on innovation and expertise required to meet specific customer or application challenges.

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The relationships with the industry are not as close as with non-food industries. However, there is increasing pressure for using food-grade lubricants from consumers, media and regulatory agencies. Lastly, there is a need for setting new benchmarks of lubricant performance.

Besides regulatory requirements, religious certifications, especially Kosher and Halal, gain importance. The certification bodies have learned that contamination is possible, which means that any ingredient – wanted or unintended – has to meet religious requirements. Therefore, more and more food producers require their lubricants to be certified.

ALARA Principle

The ALARA principle has its roots in radiation risk reduction. The core elements are source reduction, the elimination of the cause of the risk. With processing equipment, it often is not possible to leave out the process step, but it is possible to find an adequate lubricant that is H1-certified food-grade or at least food-safe. Controlling and containing are other elements and translate into good maintenance.

With well-maintained equipment, the risk of unperceived contamination is limited. Minimizing exposure time is often difficult. It may work with radiation, but is not feasible for many operations and processes in feed and food production. Maximizing the distance is difficult to implement due to area limitations and might only be feasible for building new facilities. Proper shielding is possible with many machines and should be installed already. Last but not least, a continuous optimization process keeps eyes open to potential performance improvements and risk mitigations.

Innovations in Lubricants

Food-grade lubricants have improved dramatically since the 1980s. New synthetic base oils and innovative additives helped improve performance while reducing performance shortfalls when comparing to regular lubricants. Lubricants with solid components stand out in terms of performance. Known solid lubricants such as graphite and Teflon are not applicable with food-grade lubricants.

However, ceramic components are well suitable for food applications. Ceramic particles in certain food-grade greases are chemically inert and H1 certified. In combination with minimized volumes, the risk reduction is unmatched.

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