The demands of the food processing sector present specific challenges to designers of lubricant formulas, plant lubrication engineers, lubricant marketers and equipment developers. When lubricants are able to contaminate the raw materials used in work-processes or finished products, the damaging consequences are rarely more strongly felt than in the industry of food processing.
For this reason, lubricants utilised within this sector have precise protocols, requirements and performance expectations, well beyond the demands of conventional industrial lubrication. In this article, we’ll take a closer look at food-safe lubricants, the potential risks of food becoming contaminated with non-safe lubricants and how they work. We’ll also examine how food-safe lubrication has evolved, and the specific categories used internationally that indicate the different safety levels and usages of food-grade oils.
How costly are the consequences of lubricant contamination?
While fewer recalls occur today related to lubricants because of the strict measures in place, they can still be extremely costly for companies when they happen. Many cases around the world have been well-documented. In September 2000, Stoke-on-Trent City Council confirmed that independent testing on baby food had uncovered a toxic substance. The comprehensive investigation concluded that the product made by world-leading brand Heinz was contaminated with a lubricant – a mineral oil used in production machinery. The issue was uncovered after a complaint that the product smelled like tar.
Over in the US, a serious case in 1998 saw Smithfield Foods recall around 226,796 kilograms of ham after it was contaminated with gear lubricant. Customers impacted reported extreme symptoms of experiencing a burning in their throats for a period of three hours after ingesting the meat.
How do food grade lubricants work?
Food-safe lubricants perform in the same manner as other forms of lubrication. They offer protection against friction, oxidation, corrosion and wear while transferring power and dissipating heat to cool equipment. Food-grade lubricants are also compatible with sealing materials like rubber and can even provide sealing themselves in some cases.
Lubricant types employed in the food and drink sector can often be subjected to a wide range of environmental contaminants. An example of this is in a corn milling operation, where processing generates substantial dust. While not quite as hard as dust that is silica-based, it can still present considerable problems for filtration. Meat plants require extreme steam cleaning, increasing the risk of water contamination greatly.
Another issue of lubricant contamination that can pose a potential threat to food-safe lubricants is microorganism growth, including the development of yeast, fungi and bacteria. While there is a risk from microorganisms in all industrial environments, the possibility for contamination within a food-production environment is far greater.
How food-safe lubricants have evolved
Plants operating in the food and beverage industry, as well as the cosmetic and pharmaceutical sectors, must typically run around the clock seven days per week to ensure they remain competitive and achieve optimum profitability. Breakdowns, rebuilds and shutdowns must be kept to an absolute minimum. For this reason, using the right type of lubricant in the right place can result in firms saving hundreds of thousands of pounds.
An effective food-safe lubricant cannot only avoid risks of contamination, but can also extend the life of the machinery it protects. Due to their design, many of the high-quality food-safe oils and greases can withstand extreme pressure and cold and hot water washout, and always remain in constant contact with the equipment requiring lubrication, resulting in longevity.
Food-grade lubricants are typically odourless and colourless. When they are graded H1, they are also considered harmless when trace amounts are found with the process of manufacturing and packaging. Food-safe lubricants today can be mineral-based, synthetic or semi-synthetic, with a wide range available to meet all different requirements and specific budgets.
In previous years, white mineral oil was often considered the key form on food-safe lubricants, but this is no longer the case. This is because many of its beneficial properties, like antioxidants, anti-wear characteristics and exceptionally high and low temperature ranges, are achievable now using the latest cutting-edge synthetic lubricants. While these products are more costly, the potential savings that can be gained by reduced operational downtime and increased life of equipment, such as bearings and chains, can easily outweigh these expenses.
Understanding the different NSF categories
The NSF rating is a standard system for food-grade ratings that is recognised around the world.
The NSF’s International registration categories are as follows:
H1 food-grade lubricant (also known as Incidental Contact)
This grade of lubricant is designed to be used in environments where there is a chance of contact with food, and it includes hydraulic oils, greases and other lubricants that are used in equipment for sanitising, cleaning, canning and bottling, along with blending, frying, chilling, peeling, slicing and cutting in environments that include conveyor belts, chain drives, hoses, tanks, mixers and pumps.
H2 non-food contact lubricant (also known as Below the Line)
This grade of lubricant is not intended to be used where the potential for food contact exists, but where contact may still adversely affect human health. These lubricants are not required to answer the 21 Code of Federal Regulations (CFR) requirements, but they must conform rigidly to Section 5.1 of the NSF’s established Registration Guidelines. This means they must contain no mutagens, carcinogens, teratogens, odorous substances or mineral acids, and no heavy metal may be intentionally added to their formula.
3H food-grade lubricant
This grade of lubricant covers oils that are typically edible and are used to inhibit rust on carts, hooks and other equipment that may experience contact with food during manufacturing and production.
Every product will have its own individual merits, but you’ll find high-quality oil suppliers and Industrial Lubricants surveys can assist you in identifying where and when you should use a synthetic, mineral or semi-synthetic lubricant to maximise productivity and suit your personal budget.
Leading lubrication manufacturers make oils and greases specifically for the food and beverage sector to an exacting standard, ensuring they meet all the criteria of health and safety regulators.