Food Engineering

Food-grade lubricants come of age

Past trade-offs between performance and safety have disappeared

March 7, 2012
food-grade lubricants
Food production consists of a vast array of equipment—pumps, mixers, oven chain drives, tanks, pipes, conveyor systems, compressors, automatic doors and many other units and systems. All of it needs to be lubricated properly to keep working. Plant managers know different machines require different lubricant solutions and that stocking, tracking and deploying lubricants effectively are critical to plant performance.

On one side, it’s about mechanics. Parts must move freely and be protected from friction, wear, corrosion, rust, deposits and all the other effects caused by an industrial process. Lubricants must ensure good pumpability, temperature stability (both high and low), oxidation resistance and washdown performance, as well as long replacement cycles and other factors.

On the other side, it’s about food safety. Lubrication programs in food manufacturing have to go the extra distance to ensure the safety and well-being of consumers, in addition to complying with government guidelines. Recently, a number of highly visible recalls and, in some cases, tragic food safety failures, such as melamine poisoning of milk in China and Listeria in packaged meat in Canada, have spurred increased interest in raising the food safety bar, including the choice and deployment of lubricants.

In the 1960s, USDA established three classes of lubricants used in food production applications: H1 (classified as food-grade and approved for incidental contact with food), H2 and H3. In 1998, certification responsibility transferred to the National Sanitation Foundation (now NSF International).

The limit for incidental contact for H1 lubricants remains 10 parts per million. These lubes have highly refined synthetic, mineral and vegetable bases. They can contain only approved base stocks, additives and thickeners (if grease), based on FDA Guideline Code of Federal Regulation (CFR) 21 178.3750.

H2 lubes are classified as having no possibility of contacting food. For this reason, they are not limited to a list of approved components. They still must be free of heavy metals, carcinogens, mutagens (chemicals that affect DNA), teratogens (chemicals that cause birth defects) and mineral acids.

H3 lubricants are essentially edible oils that are applied to hooks, trolleys and similar equipment to prevent rust and corrosion.

H1 lubricants are often referred to as “above the line” lubricants—used on equipment or mechanical components where there is the possibility they may drip onto the food production line below and cause incidental contact. H2 and H3 lubes, on the other hand, are often referred to as “below the line,” where there is little or no chance of the lubricant being sprayed or splashed onto the food line above.

Surprises, however, can and do occur. Once in a while, an interruption or event may happen, causing H2 or H3 lubricants to come into contact with food. This is why many processors use H1 lubricants throughout their facilities.

The challenge

Of the three types, H1 lubes are the most expensive because they are the most refined, but the added cost is miniscule in the event of a conventional spill or splash that could potentially shut down a production line or even result in a product recall.

In 1998, almost 500,000 pounds of smoked ham were recalled because of gear oil contact. In 2002, a US-based soft drink producer recalled over 3,000 cases of product that contained gear lubricant. Meanwhile, a Danish milk powder manufacturer recalled 1,100 tons of product that was contaminated by lubricant leaking through a worn axle in a gearbox. And the list goes on.

Switching to 100 percent H1 throughout a plant can eliminate such risk. But until recently, switching hasn’t been so easy. “When food-grade lubes were first introduced in the 1960s, they lacked a number of performance elements that made them unsuitable for certain mechanical demands,” says Jim Girard, vice president and chief marketing officer at Lubriplate in Newark, NJ. “Recent advancements, however, have made H1 products equal to or better than their non-food-grade counterparts. In fact, our finest-performing mineral-based hydraulic fluids at Lubriplate are also food-grade certified.”

Unlike conventional lubricants, H1 products are not potential chemical hazards and thus don’t require a HACCP program. Consequently they provide a much wider margin of food safety and worry-free production. For these and other reasons, many argue they’re not only safer, but more economical in the long run.

Synthetics gaining ground

Today’s incidental food-contact H1 lubricants are made with high-performance “white” mineral oils, either USP (which is the purest) or technical white vegetable oils and synthetic base oils such as polyalphaolefins (PAOs), polyalkylene glycols (PAGs) and esters. These highly refined base oils, coupled with new H1-additive packages, can deliver premium performance.

Tyler Housel, lubricants business director at Inolex in Philadelphia, PA, recently published a white paper on esters. In it, he explains that esters—the basic building blocks of all ester-based synthetic lubricants—are made by reacting an acid with alcohol, and that an endless variety of esters can be manufactured. By combining an NSF HX-1 ester with HX-1 additives, the lubricant can be approved for incidental food contact (NSF category H1). By choosing the ester and additives wisely, the lubricant can be engineered to provide any production and performance characteristics a producer desires.

“If you can use a natural ester, such as a vegetable oil, and it works for you, I’d never tell you to switch,” says Housel. “But natural esters have a limited temperature range, meaning at temperatures above 200°F they can create sludge, gum, smoke, off-odors and deposits. The advantage, of course, is if edible vegetable oil falls on your food product, the food is still perfectly edible. In some cases, however, it is important to note that even vegetable-based lubricants may be inedible because of the additives. Food-grade NSF H1 lubricants are approved for incidental contact and not direct, intentional content.”

But in cooking applications, especially baking, temperatures inside the oven can reach 500°F or more, so natural esters won’t work as lubricants for the conveyor drive chains. The same holds true for low-temperature environments, such as coolers and freezers. “The wrong lube will cause equipment to chatter, squeal, freeze up or wear out, and the line to eventually break down,” says Housel. “Synthetic NSF H1 lubes, however, will stay the course and actually save money over the long term by increasing lubrication intervals by up to five times.” Not having to change lubes as often reduces the chance of contamination and results in less waste.

H1 vegetable oils

Some companies manufacturing vegetable-based lubes are pushing the envelope. Plews & Edelman of Dixon, IL manufactures bio-based H1 UltraLube oils and greases. “With our products, you’re getting a synthetic level performance, at a petroleum level price,” says Dave Babics, senior product manager, lubrication products.

For instance, the UltraLube family contains an H1 NLGI Grade 2 grease that has a drop point rating of 523°F, which is in the synthetic range. “That’s the point where the grease gets so soft it no longer can function as a thickened lubricant,” says Babics. “In normal production, you want to stay about 100 degrees below that.” On the other end of the scale, this particular oil has a low-temperature rating of 32°F, well above the much colder temperatures synthetic lubricants can endure. The company is currently awaiting NSF approval of a new H1 grease with a temperature range between -30°F and 350°F, specifically for cold environments and automatic lubrication systems.

Bio-based lubricants can also leave a thin layer of film on interior metal surfaces once the machine has been turned off. This reduces wear during the next start-up. UltraLube vegetable oil lubricants have been given the USDA’s BioPreferred designation (see www.biopreferred.gov) based on their biodegradability and lack of harsh additives that can cause skin irritation and other problems.

Like vegetable-based oils and greases, ester-based synthetic lubricants form a micro-thin film on the metal surfaces they are in contact with. “The ester fluid film creates a cushion of sorts that reduces friction, saves energy and protects the metal surfaces,” notes Housel.

Summit Industrial Products of Tyler, TX was the first company in North America to be registered by NSF and second in the world to be ISO 21469 certified. Market Manager Ike Texler notes: “Synthetics are the epitome of what you want in a lubricant. They provide the longest intervals between service and the best wear protection.”

Not all that glitters is gold, notes Jim Girard. “A thing to watch out for is the many lubes claiming to be 100 percent food-grade when they’re not.” The best way to be sure is with a letter from the NSF, or CFIA in Canada, stating the product is, in fact, food-grade and a similar letter from the manufacturer which is called “A Letter of Guarantee.” (An approved list of food-grade lubricants is available at www.nsf.org.)

Packaging is another consideration when choosing a lubricant. For instance, the most common container for fluid lubricants in the food industry is the 55-gallon (208-liter) steel drum. “Make sure your supplier is using new drums and not refurbished ones,” says Girard. “The simple reason is purity. Used drums create a greater risk of contamination depending on who used them last.”



Lube surveys

Monitoring the use of packaging, along with what is and what isn’t a true H1 product, is part of a lubrication survey. Surveys not only improve food safety, they also save money. “In one case, a potato processor was struggling with an auger bearing they had to change every four to six weeks. We put SumTech FGCO in there, and it’s been over a year and a half since they’ve changed the bearing,” says Texler. In another case, a dairy in Idaho used to change the oil in one of its separators every six to eight weeks. By switching to Summit’s Syngear FG Series it extended change intervals to six months instead, Texler states.

Eric Peter, president of JAX INC., Menomonee Falls, WI, says his company has a “Lube-Guard” program that uses color-coded wall charts, equipment tags and container labels to help ensure products are used for the proper application. “We also have an oil sampling program to help our customers get the most life out of their lubricants,” he notes.

Sprayon Products of Cleveland, OH has a coded visual program in place as well. It’s called 5S Visual Management: “All of our products are integrated with this identification system—it integrates the labeling on Sprayon product packaging with a unique set of identification tools to help manufacturing facilities accurately deploy the use of chemicals and lubricants,” says Sprayon Associate Product Manager Mark Greenwell. “We also have Eco-Grade and Liqui-Sol programs to help facilities operate more safely without sacrificing performance.”

Sprayon offers 14 H1 lubricants for demands such as heavy load pressures and superior resistance to water washout, lower flammability ratings and wide temperature ranges.

Robert Farthing, category portfolio manager, specialty fluids, at Petro-Canada Lubricants in Mississauga, Ontario, says food production applications are a key part of his company’s business. The company has a full line of lubricants and greases, food-grade mineral oils and a selection of PURITY FG greases.

PURITY FG with MICROL is unique in its ability to inhibit the growth of micro-organisms that can cause product degradation and odors. “We’ve also introduced a line of EcoSia products that are completely non-toxic and inherently biodegradable to help customers achieve their environmental goals,” explains Farthing.

CITGO Petroleum Corp, Houston, TX, produces conventional and synthetic lubricants including Clarion food-grade products. The company also provides a fire-resistant food-grade lubricant specifically for hydraulic systems. “This product is used in applications where fire risk concerns prohibit the use of a conventional hydraulic fluid, such as deep frying operations,” notes Clarion Lubricants Product Manager Benjamin Briseno. “Another noteworthy product is our line of Clarion SynBar barrier fluids. These are effective where mechanical seals are used to keep food product separated and ensure purity during the manufacturing or handling process.”

Demand on the rise

Glen Sharkowicz, global business development advisor for ExxonMobil Fuels, Lubricants & Specialties Marketing Company in Fairfax, VA, points out that greater demands have been made on lubricants from food and other industries and that these demands will continue to increase in the future. “As technology progresses, production machines of all sorts are getting smaller, lighter, faster, and consequently work at higher temperatures,” he says. “This also means the amount of lubricant used by a typical machine is decreasing, while load is increasing. Think of more power going through a smaller gearbox. This stresses the lubricant and is why companies such as ours dedicate significant resources to ongoing product development to keep up with changing trends.”

This led to the launch in 2007 of ExxonMobil’s Mobil SHC Cibus H1 lubricants, the company’s product line of synthetic lubricants. “Mobil SHC Cibus lubricants can offer up to 3.6 percent energy savings particularly for gearboxes, depending on the application. Over many gearboxes, that can amount to significant benefits—both for the bottom line and the environment,” notes Sharkowicz. The company also sells a line of NSF H1-registered Mobil SHC Polyrex synthetic greases which, like their fluid counterparts, are noted for long life, maximum equipment protection, less used lubricant to dispose of, high-temperature capability and resistance to oxidation.

For instance, in Europe, a sugar beet processing facility replaced conventional grease in a steam dryer with Mobil SHC Polyrex 462 grease, which is particularly suitable to high temperatures. “In one unit alone, the company saved $20,000 dollars in annual operating expenses, and reduced bearing failures,” says Sharkowicz.

Considering 65 percent of plant stoppages and equipment failures are the result of improper use of lubricants, extra efforts to keep a tight ship won’t go unrewarded. An ounce of prevention is worth more than a pound of cure—not only in day-to-day operations, but also in the much more important area of food safety. 
 

SIDEBAR 1

Sweet solution for drinks processor
Bel-Ray Company Inc., Farmingdale, NJ, solved a major problem at a global drinks processor in Thailand with its No-Tox H1 Sugar Soluble lubricant. The processor’s sugar warehouse is situated across the road from the filling plant and transporting the sugar was a problem. It mixed with the lubricant the processor was using and created a black, sticky residue on the chains. Not only did the lubricant have to be replaced every four days, the chains had to be replaced every two months due to wear.

Bel-Ray’s No-Tox H1 Sugar Soluble lubricant dissolves the sugar, while leaving behind an invisible coating to prevent the sugar from sticking. The product’s low viscosity enables full penetration. The result? Chains only need lubricating every month instead of every four days, and replacing once per year instead of every two months. The company is enjoying annual savings of $33,000 on the chains alone, not to mention further savings from lower lubricant usage and maintenance.


SIDEBAR 2

The following companies supply food-grade lubricants:

Aerospace Lubrication
www.aerospacelubricants.com

Bel-Ray Company, Inc.
www.belray.com

Chemetall
www.chemetallamericas.com

Clarion
www.clarionlubricants.com 

Exxon Mobil Lubricants & Specialties
www.mobilindustrial.com 

Fuch Lubritech
www.fuch.com
Haynes Manufacturing Company
www.haynesmfg.com 

Inolex
www.inolex.com

JAX, Inc.
www.jax.com

Kluber Lubrication
www.klubersolutions.com 

Krylon Products Group
www.kpg-industrial.com

Lubrication Engineers, Inc.
www.le-inc.com
Lubriplate
www.lubriplate.com

Petro-Canada, Inc.
www.lubricants.petro-canada.ca

Plews & Edelmann
www.plews-edelmann.com

Schaeffer Manufacturing Co.
www.schaefferoil.com

Sprayon
www.sprayon.com

Summit Industrial Products
www.klsummit.com
Total Lubricants
www.total-us.com 

Ultrachem, Inc.
www.ultracheminc.com