The importance of suitable materials for food contact in precision balls

Essential requirements for food contact materials

Precision balls made from certified materials offer regulatory compliance, strength, durability and safety throughout the entire supply chain.

In the food & beverage sector, these components must meet very strict requirements:

• chemical inertness, to prevent the release of harmful and undesirable substances
• corrosion resistance, even in humid environments or in the presence of aggressive detergents
• sanitisation, essential for reducing microbiological risks
• regulatory certification, compliant with European and international standards.

The regulatory framework is divided into two levels: on one hand, general regulations on safety and hygiene, and on the other, specific technical standards for individual materials.

European regulations: the MOCA reference

In Europe, materials in contact with food (MOCA) are regulated by Regulation (EC) 1935/2004, which establishes certain fundamental principles:

• they must not constitute a hazard to human health
• they must not alter the composition, odour, taste or colour of food
• they must be accompanied by a declaration of compliance and traceability.

This is accompanied by specific provisions such as EU Regulation 10/2011 for plastics, Directive 84/500/EEC for ceramics and Directive 2007/42/EC for cellulose foils. For metals, in the absence of harmonised standards, the reference in Italy is still Ministerial Decree 21/03/1973 and subsequent amendments.

FDA: criteria for the US market 

In the United States, food-grade materials are regulated by the FDA (Food and Drug Administration) through CFR Title 21.

The FDA distinguishes between:

• GRAS (Generally Recognised As Safe): materials with a consolidated use
• FCN (Food Contact Notifications): mandatory notification for new substances
• FAP (Food Additive Petitions): rigorous procedure for materials that intentionally migrate into food.

Austenitic stainless steels (AISI 304, 316, 316L) are recognised as GRAS..

Certifications required from manufacturers

Official certifications and tests are required to market suitable components:

• MOCA declaration of compliance (mandatory in the EU), with identification of material, regulatory references, conditions of use and manufacturer’s signature;
• Global and specific migration tests to assess any release of substances from materials into simulated foods and the presence of toxic metals (e.g. lead, cadmium, nickel);
• FDA certifications for export to the USA;

ISO quality certifications to guarantee controlled and traceable processes.

Compatible materials for food-grade precision balls

The choice of materials for food contact must balance mechanical properties, chemical inertness and resistance to harsh conditions..

Stainless steel: the standard for food

Austenitic stainless steels remain the main reference, thanks to their excellent corrosion resistance and compatibility with the main cleaning agents:

• AISI 304: 18% chromium and 8-10% nickel, offers good resistance to oxidation, corrosion and detergents.
• AISI 316 / 316L: a more resistant variant, thanks to the addition of 2-3% molybdenum, particularly suitable for acidic or chloride-rich environments (e.g. salty foods, sauces, brines).

The stainless steel balls produced by RGPBALLS are finished using techniques that reduce surface roughness, limiting the adhesion of organic residues and microbiological risks.

Advanced technical ceramics for extreme resistance

Technical ceramics are the ideal choice for high-performance applications, thanks to their extremely hard crystalline structure and complete chemical inertness. They are suitable for abrasive, acidic or high thermal shock environments.

More specifically:

• Zirconium oxide (ZrO₂): more wear-resistant than steel, ideal for pumps that handle abrasive fluids (e.g. juices with pulp, purées, thick sauces).
• Silicon nitride (Si₃N₄): lighter than steel, excels in thermal shock resistance and dimensional stability, often used for high-performance hybrid bearings.

Food-grade certified plastics

When certified for food use, polymeric materials are used in specific applications, especially those involving low loads and low speeds.

The main ones are:

• Polyacetal (POM): semi-crystalline thermoplastic with good mechanical properties and wear resistance. Used in guides, rollers and lightweight components for food conveyors.
• PTFE (Teflon®): a fluorinated polymer with almost absolute chemical inertia and one of the lowest coefficients of friction, it is ideal for aggressive environments or those requiring reduced lubrication.
• Polypropylene (PP): economical and easy to process, it withstands temperatures of up to approximately 100°C. Excellent for disposable or semi-disposable components, containers, valves and small parts.

Some advanced engineering polymers, such as PEEK, can also be used in more extreme conditions (high temperatures, medium loads) but involve higher costs and more complex processes.

Contamination risks and control systems

Choosing a material that is not suitable for food applications can lead to chemical migration, resulting in food contamination. And even when compliant and inherently safe materials are used, hazards can arise during processing, storage or use.

Inspection and monitoring along the supply chain

Contamination prevention requires systematic controls at every stage of production:

• Raw materials: supplier qualification and auditing, acceptance analysis, segregation between certified and standard batches.
• Production: preventive cleaning, dedicated lines, cross-contamination prevention procedures, fluid monitoring.
• Post-production: final cleaning, laboratory testing, suitable packaging and full traceability.

RGPBALLS integrates internal chemical and microbiological controls to ensure that each batch complies with the most stringent standards.

Applications of food-grade balls in the food industry

Precision balls made from food-contact materials are used in a wide range of machinery and systems, including:

• Food-grade pumps (centrifugal, volumetric, hygienic-sanitary)
• Bottling valves and industrial fittings
• Mixers and mills for flour, spices and powders
• Packaging machines (filling, labelling, capsuling machines)
• Pasteurisers, homogenisers, separators
• Dough mixers and rolling mills
• Handling and transport systems

In all these instances, the combination of resistance, chemical inertness and regulatory compliance ensure production continuity and food safety, even in intensive processes.

RGPBALLS: certified materials for a safe food supply chain

For RGPBALLS, MOCA and FDA compliance is a real competitive value.

Each precision food-grade ball is manufactured from materials certified for food contact, laboratory tested and tracked throughout the supply chain.

This enables customers to reduce contamination risks, ensure food safety and comply with increasingly stringent regulations.

Would you like to know how certifications can improve your company’s competitiveness? Read our dedicated article

Do you want to reduce contamination risks and increase the reliability of your equipment?

Choose RGPBALLS precision balls

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