What are food-grade lubricants?

How can a lubricant become a food additive? Whether through leaks, excessive lubrication or messy application during maintenance, food-grade lubricants can inadvertently become indirect food additives. In today’s fast-paced production environment, lubrication safety audits, selecting and implementing premium-quality food-grade lubricants and proper lubrication programs are all proactive steps towards a safe, efficient and hygienic processing facility, all while increasing profitability.

A lubrication safety audit should be performed every three years, ensuring proper equipment lubrication, improved performance and the opportunity for lubricant consolidation, thus lowering the cost of inventory and the misapplication of lubricant. A plant survey should be conducted when changing lubricant vendors and every time new machinery is added to the production line. A survey also exposes handling and storage procedures, various environmental concerns (all of which can lead to lubricant contamination) and process equipment contamination, potentially averting disaster for food and beverage manufacturers.

Understanding the rules

An oil or grease qualifies as an NSF H1 food-grade lubricant when, in the event of a contamination, it is present in no more than 10 mg/kg of the foodstuff in question and does not cause any physiological hazard or affect the food’s odour and taste in any way.

Food-grade lubricants have been in service since the early 1960s. Prior to 30 September 1998, approval and compliance of food-grade lubricants was the responsibility of the USDA. The following are category code definitions of H1, H2, 3H, H3 and HT1 lubricants provided by NSF International, the standard which has replaced the now-defunct USDA H1 rules, procedures and systems for lubricants.

H1 — lubricants with incidental food contact (so-called food-grade lubricants)

Preparations permitted for use as lubricants and antirust agents (or as release agents on gaskets or seals of tank closures), where there is possibility of incidental food contact, must be formulated in compliance with CFR, Title 21, Section 178.3570 and other sections referenced therein. The amount used should be the minimum required to accomplish the required technical effect on the equipment so treated. When a product is used as an antirust film, it should be removed by washing or wiping before putting the equipment back into service.

H2 — lubricants with no food contact

These products are used on equipment and machine parts in locations where there is no possibility of the lubricant or lubricated part contacting edible products. There is not a specific list of substances that may be used as lubricants where there is no possibility of food contact. Most substances generally used for the purpose in industry would be acceptable. Substances that are categorically unacceptable for such use are listed among the substances in Part 5.1 of NSF guidelines. There may be other substances that are not acceptable because of unfavourable toxicology or other considerations. Therefore, each preparation will be evaluated on its own merit.

3H — release agents

These products are used on grills, loaf pans, cutters, boning benches, chopping boards or other hard surfaces in contact with meat and poultry food products to prevent food from adhering during processing. Products containing edible oils — such as corn oil, cottonseed oil and soybean oil — mineral oil complying with 21 CFR, Section 172.878 and other GRAS substances may be acceptable upon review by NSF. In addition, defoaming agents complying with 21 CFR, Section 173.340 (a)(1) and (a)(2) may be acceptable.

H3 — soluble oils

These products are used to prevent rust on hooks, trolleys and similar equipment. Treated equipment which contacts edible products should be cleaned by washing or wiping before putting the equipment back into service. Products may be composed of any of the following:

• Edible oils (corn oil, cottonseed oil, soybean oil) complying with 21 CFR, Section 172.860;
• Mineral oil complying with 21 CFR, Section 172.878;
• GRAS substances complying with 21 CFR, Parts 182 (multipurpose only) or 184.

HT1 — heat transfer fluids with incidental contact

These products are used as heat transfer fluids in primary and secondary heating and cooling systems in food processing facilities. Preparations permitted for use as heat transfer fluids, where there is possibility of incidental food contact, must be formulated in compliance with CFR, Title 21, Section 178.3570 and other sections referenced therein; ingredients may also comply with CFR, Title 21, Part 172. The amount used should be the minimum required to accomplish the required technical effect on the equipment so treated.

When recommending and/or using food-grade lubricants they should comply with NSF International H1, the standard that replaced USDA systems for lubricants where incidental contact with food is likely. For a complete list of food-grade lubricants registered with NSF in all classification categories, see the NSF website.

Food-grade lubricants should comply with the technical qualifications published in the Federal Register, FDA 21CFR, 178.3570, as well as with FDA standards for raw materials used in food-grade products (such as lubricants) within the United States, including imports and exports. Food-grade H1 products are manufactured from components that have been evaluated and approved by the US FDA and declared safe for use in food processing preparations. The maximum concentration of a lubricant allowed in food is 10 ppm (parts per million). Most premium-quality H1 lubricants are Kosher and Pareve approved as well as Halal certified.

NSF H1/food-grade lubricants play a key role in Hazard Analysis Critical Control Point (HACCP) programs. In the United States, the FDA and USDA demand beverage and other food processors develop HACCP programs. However, if these processors use 100% NSF H1 food-grade lubricants then they are not required to have a HACCP plan with their lubrication program, since NSF H1 lubricants are not considered potential chemical hazards.

Myths and misconceptions

Many products for the food industry are referred to as food-grade, but it is important to know that only NSF H1 registered lubricants are truly ‘food-grade’. There are misleading marketing claims that white lithium grease is food-grade. However, lithium-thickened grease is not accepted as food-grade H1 and does not comply with NSF category code H1. When discussing food-grade lubricants, refer to the H1 category code. There has always been the misconception that food-grade lubricants do not perform as well. This may have been true in the past, but today there are food-grade lubricants that perform as well as non-food-grade lubricants and, in many instances, offer better performance than conventional lubricants.

All lubricants, including food-grade lubricants, need to provide proper lubrication for metal-to-metal surface separation. Antiwear performance, extreme-pressure/high-load-carrying properties, oxidation stability, rust and corrosion inhibitors, good seal compatibility and the ability to perform in temperature-extreme environments are paramount. They must withstand a broad range of contamination sources, such as process water, steam, high-pressure water cleaning/sanitation and acidic conditions. Other contaminants food-grade lubricants must withstand include chemicals, sugar and substances that are present in the manufacturing process.

Acceptable H1-approved lubricant base stocks can be either mineral or synthetic. Mineral oils used are either technical white mineral or USP-type white mineral oils. Synthetic lubricant base stocks are usually polyalphaolefins (PAO) or polyalkylene (PAG). These base stocks are primarily used in lubricants designed for temperature extremes. Dimethylpolysiloxane (silicones) with a viscosity greater than 300 centistokes is also permitted.

Acceptable H1-approved grease-thickening agents are aluminium stearate, aluminium complex, organo clay, polyurea and calcium sulfonate complex.

Sam Hall is the Industrial Technical Service Manager for Bel-Ray Company. He has 40 years of experience in lubricant production management, plant maintenance, lubricant sales management and industrial technical service. He has conducted numerous lubricant sales training seminars, plant lubrication surveys and audits, has been a guest speaker at the NORIA Lubrication Excellence Conference and is a member of STLE.

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