Choosing the Right Lubricant
January 1, 2005
Choosing the Right Lubricant
It is no longer a matter of choosing between food-grade and non food-grade lubricants; the question for processors is whether to use a synthetic or mineral-based lubricant.
Machinery and equipment leak. It’s a fact. Regardless of its application, normal wear and tear on equipment seals cause hydraulic systems to release miniscule quantities of oil that may come into contact with a batch of food. Under FDA regulations, processors using non food-grade lubricants must not allow the lubricant to come into contact with the food, and if contact occurs, the entire batch must be discarded. The threat of losing an entire batch of product is the reason the bulk of processors have turned to food- grade lubricants, as the FDA allows food-grade lubricant contamination to be a maximum of 10 parts per million.
Today’s food-grade lubricants are wonder products. In addition to complying with health and safety regulations and being compatible with a machine’s seals, the lubricants must provide protection against oxidation, wear, corrosion, and friction. These characteristics are just the start for food-grade lubricants. While all lubricants must protect, comply, and be compatible, superior lubricants must be able to withstand increased equipment operating speeds and improve plant uptime.
Processors demand a lot from their food-grade lubricants. Mineral- or petroleum-based lubricants had served as the industry standard, but synthetic lubricants that have been engineered for superior performance are replacing them. These synthetic lubricants, which are tasteless, odorless, and non-toxic, have been designed to maximize equipment life, as well as reduce maintenance and the frequency of lubrication for equipment components. When comparing synthetics to mineral oil-based lubricants, synthetics typically have lower pour points, a higher viscosity index, and better oxidation stability.
Pour points are the lowest temperature at which a lubricant will retain its viscosity before it will not flow anymore; therefore, the colder the operating temperatures are, the greater the risk of compromised lubricant performance. Synthetic lubricants have lower pour points than their mineral counterparts, so not only can the equipment run at a colder temperature — but also the synthetic lubricants ensure equipment performance in this type of environment.
Cold is not the only radical environment at a processing facility. Synthetic food-grade lubricants have higher viscosity indices than their mineral-based counterparts. They will exhibit less change in viscosity at higher and lower temperatures than mineral-based formulations. This helps reduce inventory for the processor looking to simplify their operations. Synthetics have the benefit of better oxidation stability when formulated with a proper anti-oxidant in comparison to mineral oil formulations. The benefit to the end-user is a fluid that will last longer thereby helping to reduce oil changes and plant downtime.
NSF authorization program
As lubricant properties continue to improve, so does the way in which food-grade lubricants are authorized. The industry standard had been the USDA/FSIS authorization program; however, the NSF program mirrors the USDA/FSIS program and offers additional benefits.
NSF registration reviews the lubricant formulations and certifies that the lubricants are in compliance with the various FDA Title 21 regulations. NSF registration also covers lubrication labeling. For labeling, the name of the product, the manufacturer’s name, category code, and directions regarding use must be displayed. Also, the directions for use must state the minimum amount of lubrication required to achieve the operating equipment’s purpose or technical effect.
Under the traditional USDA/FSIS system, lubricant suppliers were on the “honor system” to resubmit products if there were formulation modifications to the lubricants. However, in the NSF program, lubricant’s formulations are continually monitored for effectiveness. Different from the USDA/FSIS program, there are fees for NSF evaluation and registration. NSF says the fees are designed to make the lubrication supplier responsible for making sure its lubricants are created with FDA Title 21-approved ingredients. Additionally, NSF’s fees are steep so as to discourage radical or outrageous submissions from suppliers.
On the horizon
While many processors have either made or are making the switch to synthetic lubricants, there are still innovations to be made, especially on the mineral-based oil side. One new product worthy of mentioning is bearing grease formulated with white oil. White bearing grease, a white oil-based grease, is formed from a unique mix of an aluminum complex thickener, white lubricating solids, and other additives. This type of bearing grease is designed to reduce equipment friction, minimize wear in food-grade applications, and prevent metal-to-metal contact.
A benefit of this particular bearing grease is that because the raw materials have been chosen to be used in mechanisms where incidental contact with food products is possible, it can be used in process machinery in meat processing plants.
Food-Grade Lubrication Categories
NSF/USDA H-1 authorized lubricants are permitted on equipment where food may potentially be exposed to the lubricated part of the machine. USDA and FSIS refer to these instances as incidental contact.
NSF/USDA H-2 authorized lubricants usually contain nontoxic ingredients and may be used in processing plants on equipment in locations where there is no possibility of the lubricant or lubricated part of the machine to come into contact with products designated for consumption.
NSF/USDA H-3 refers to water-soluble oils. When using H-3, the machined part must be cleaned and free of the emulsion before reuse.
NSF/USDA P-1 is for lubricants that are used in accordance with the conditions established by the USDA’s letter of acceptance. P-1 lubricants should not be used in a food-processing plant.