Any contamination could be extremely costly—potentially endangering human health, resulting in expensive recalls or irreparably damaging a business’ reputation.

Besides offering the usual protection characteristics demanded by modern lubricants such as wear resistance, reduced friction and anti-corrosion properties, they must also be resistant to bacteria, fungal growth, water and high temperatures. Importantly, food-grade lubricants must be inherently safe in case they ever come in contact with the food itself. 

As food production increases, the food-grade lubricants market is tipped for robust demand growth over the coming years, said Ismael Martinez, manager of certification for the nonfood compounds team at Ann Arbor, Michigan-based certification body NSF.

Lubricants used where food is manufactured, processed or prepared are governed by three distinct categories: H1, H2 and H3. H1 lubricants are those suitable for incidental contact with food and must be manufactured using approved ingredients. H2 refers to lubricants that can be used in the food processing facility, but they cannot be used in the food processing area and have no likelihood of coming into contact with food. Lastly, H3—also known as soluble or edible oils—applies to lubricants commonly used on food processing equipment, such as hooks and trolleys.

H1 registrations in NSF’s White Book™ listing continue to rise by around 7% each year, added Martinez. The White Book is a trusted and definitive source of all nonfood compounds for the food industry, verifying that a lubricant’s ingredients and composition are safe for use in a specific application.

For those seeking greater assurances, the internationally-recognized ISO 21469 program is seen as a step up from NSF registration and is the leading global standard for food-grade lubricants. 

This certification includes a more robust evaluation of food-grade lubricants with an audit of the manufacturing facility, product testing and a thorough risk assessment. The remit of the ISO program also extends beyond the food and beverage industry, covering pharmaceutical, cosmetics, tobacco and animal feed industries as well. 

The food industry faces several challenges that could affect lubricant manufacturers moving forward, with the safety of all lubricant formulations constantly being re-evaluated, Martinez said.

NSF and other bodies around the world continue to monitor and assess the potential risks and implications to human health from per- and polyfluoroalkyl substances, more commonly referred to as PFAS. (Be sure to check out Mary Moon’s feature article on Page 20 for more information on PFAS.)

These so-called “forever chemicals,” used in applications ranging from grease proofing agents to product packaging, have long been the subject of concern. In fact, investigations are ongoing to establish whether they can contaminate food and pose a health and safety risk.

“There are already restrictions popping up in the U.S., with certain states implementing restrictions, and we’re starting to see real-life impact,” Martinez noted.

“PFAS is not quite defined yet, and a lot of work still needs to be done to really identify the extent to which it needs to be controlled,” he said. “These chemicals can be used in food-grade lubricants, so this is a big concern for manufacturers—having to come up with a solution that may have to meet these potential restrictions.”

Similarly, the presence of mineral oil-saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) remains a pressing issue in Europe, with stronger controls being considered. In 2012, a European Food Safety Authority (EFSA) panel determined that these substances could pose a potential risk to human health, and they have been closely monitored and reviewed ever since.

“There’s still some confusion and concern from food manufacturers about what’s down the road for MOSH and MOAH, as this could really impact their businesses,” Martinez said. “Some in the industry think that the restrictions are premature and that further investigation is needed. NSF is tracking this issue closely.”

He added that “there are concerns about public health, and part of the issue is it’s still not completely clear what the long-term impacts of exposure would be.” 

EFSA published an update of the risk assessment of mineral oil hydrocarbons in food in September this year that recommended further data collection and research was needed to make any concrete conclusions.

“NSF is closely monitoring these situations,” Martinez said. “Once we have a better idea of the different criteria and know what the restrictions are, we can then step in and offer support to our clients, whether that’s testing, formulation reviews or other types of evaluation.”  

According to a recent report published by market research firm P&S Intelligence, the food-grade lubricants market is expected to total $516.5 million by the end of the decade. With demand for food increasing and the awareness of food safety growing, the appetite for food-grade lubricants is therefore expected to rise in the years ahead, too.

In this Spotlight, LANXESS explains how its food-grade greases are ideal for use in complex food processing environments.  

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Food-Grade Greases Built to Withstand Food Processing Environments

Modern food and beverage production/processing facilities prioritize several key factors, including production efficiency, waste reduction, cost savings and ensuring consumer safety.

These plants undergo frequent cleaning procedures, extensive water washdowns, and operate across a broad temperature range that includes both high heat and cold conditions. Additionally, their processes often involve the presence of sugar, dust or water, collectively creating a demanding and rugged environment that places heavy-duty demands on lubricating greases.

Selecting the right grease is critical to ensure equipment reliability, productivity and compliance with food safety regulations. 

Here are some key factors to consider when choosing a grease for such a demanding environment:

• Water resistance: Given the frequent water wash downs and cleaning, the grease must have excellent water resistance to prevent washout and maintain its lubrication properties even in wet conditions. 
• High-temperature stability: In food processing, some equipment may be exposed to high temperatures during cooking, baking or sterilization processes.
• Corrosion protection: The presence of water, acids and other corrosive substances can lead to equipment corrosion. Greases with good corrosion protection properties can help to extend equipment life and reduce maintenance costs.
• Heavy-duty load-carrying capacity: Equipment in food processing may operate under heavy loads and extreme pressure conditions. Greases with high load-carrying capacity are ideal for heavy-duty applications.
• Resistance to contaminants: Food processing environments can be exposed to various contaminants, including food particles, dust and chemicals. Greases with good resistance to contaminants will maintain their lubricating properties and protect equipment surfaces from wear.
• Compatibility with sealing materials: In food processing equipment, elastomers and other sealing materials are commonly used to prevent contamination and leaks. It is essential to ensure the selected grease is compatible with these sealing materials to avoid potential issues.
• Maintenance and reapplication intervals: Regular water wash downs and harsh conditions can impact grease life. Choosing a grease with a longer service life or reapplication intervals helps to reduce maintenance frequency and downtime.
• Food-grade compliance: For applications where there might be incidental contact between the grease and food products, it is important to use food-grade greases that meet regulatory requirements. Certain formulations of calcium sulfonate, aluminum complex and lithium complex greases can be made to comply with food-grade standards.

Considering these factors, LANXESS’ G-2000 food-grade calcium sulfonate complex greases are regarded as the preferred choice for these complex food processing environments (see Table 1). 

Table 1. LANXESS grease demonstrates exceptional load carrying, corrosion/wear/water resistance

While most other thickener types rely upon added anti-wear agents or additives to provide protection, the exceptional anti-wear properties of LANXESS’ calcium sulfonate complex technology comes directly from the calcite form of calcium carbonate found within the thickener structure. Four-ball wear scars of less than 0.5 millimeters are typical for LANXESS G-2000 greases, which helps to extend component life. Calcium Sulfonates do all of this without being unnecessarily loaded with additives. 

Typical weld loads for the G-2000 greases are 400-500 kilograms—although LANXESS also manufactures G-2000 greases with weld loads as high as 800 kilograms.

Calcium sulfonate complex grease is exceptionally shear stable, even in the presence of water and heat. Shear stability is critical to ensure the grease remains at or near its original consistency throughout its life in an application. 

Mechanical stability of a grease is a function of temperature. Simply because a specific grease has good mechanical stability or shear stability at 25˚C does not guarantee that it will have good mechanical stability when sheared at elevated temperatures like those experienced in actual use. 

A perfect example is aluminum complex greases, which generally have acceptable shear stability at 25˚C. Worked 100,000 stroke pens and the standard two-hour roll stability test (run at 25˚C) will generally be acceptable. However, run that AlX grease on a roll stability test at 150˚C, and softening of 80 to 100 points will always happen. If run for six hours rather than two, it will result in a fluid devoid of any measurable grease structure. 

Table 2. LANXESS Calcium Sulfonate Complex Greases demonstrate exceptional characteristics compared to alternatives.

The good news is that Ca Sulf-X greases do not have this problem. However, some can harden when sheared at high temperatures for prolonged periods and then allowed to cool. This effect appears to be related to the base oil used to make the grease, rather than the thickener itself. 

LANXESS calcium sulfonate complex grease typically loses less than 1% in the ASTM D1264 water washout test at 79˚C. This keeps consumption low and is particularly critical in food processing plants where frequent cleaning is needed, as it limits the amount of grease that comes into contact with food.

LANXESS has been developing calcium sulfonate complex greases since the 1980s and offers over 300 formulations, including a wide range of food-grade greases—first produced in 2001—that are NSF H1 registered, Kosher and Halal certified.

To find out more about LANXESS food-grade lubricants and how our products can meet the needs of your application, visit our website at http://lab.lanxess.com.