Food Grade Plastic in Food Processing: A Guide to Choosing Materials for Food-Contact Parts

A scraper blade that cracks mid-shift. A conveyor guide that wears down and sheds fragments onto the line. A cover that turns cloudy and pitted after a few months of daily sanitizer washdowns. In food processing, a failed plastic part is more than a replacement order. It can mean a contaminated batch, a recall, or a production line sitting idle. That’s why food grade plastic is one of the first things we talk about when a food and beverage equipment manufacturer brings us a new part.

As part of our industry series, this post walks through what food grade plastic actually means, where it shows up in food processing equipment, which resins are commonly used, and what to ask your molder before a mold is ever cut.

What Makes a Plastic Food Grade?

“Food grade” isn’t a single material or a stamp on a bag of pellets. In the United States, a food grade plastic is generally a resin formulation that complies with FDA regulations for food contact. For most polymers, those rules live in 21 CFR 177.

The key word is formulation. Compliance covers the base resin and everything compounded into it, including colorants, fillers, and other additives. The same polymer can be sold in one grade that’s compliant for food contact and another that isn’t. Swapping in a different colorant or additive package can change a material’s status entirely.

A few other terms come up often in food contact materials conversations:

• FDA compliant: The resin formulation meets FDA requirements for its intended conditions of use.
• NSF/ANSI 51: A standard for materials used in commercial food equipment, often requested by equipment manufacturers selling into foodservice.
• EU 10/2011: The European regulation for plastic food contact materials, relevant if your equipment ships overseas.

Conditions of use matter, too. A resin that’s compliant for room-temperature dry goods may not be compliant for hot, fatty, or acidic foods. Contact time and temperature both factor in, so it’s worth defining those early.

Food Contact vs. Non-Contact: Not Every Part Needs the Same Grade

Not every plastic part on a piece of food processing equipment touches food. Sorting your parts into categories early can save money without cutting corners.

• Direct food contact surfaces: Scoops, scrapers, nozzles, hoppers, and guides that touch the product itself. These need a documented food grade plastic.
• Splash zone parts: Components near the product that may see incidental contact or spray. Many OEMs treat these like contact parts to stay on the safe side.
• Non-contact parts: Housings, brackets, handles, and covers away from the product zone. These may not need food grade material, but they still face the same harsh cleaning chemicals as everything else.

Knowing where each part falls helps your engineering team and your molder pick materials that fit the job, rather than over-specifying every component.

Choosing a Food Grade Plastic: Common Resins and Where They Fit

When engineers ask “is this plastic food safe?”, the honest answer is usually “the right grade of it is.” Here’s how some common resins stack up.

Is polycarbonate food safe? FDA-compliant polycarbonate grades are available. PC offers impact strength, heat resistance, and optical clarity, which makes it a strong fit for guards, covers, and sight windows on food and beverage equipment. One thing to know: polycarbonate is made using BPA. If your application needs to be BPA-free, PC may not be the right choice.

Is nylon food safe? Compliant nylon grades exist, and nylon’s wear resistance makes it a workhorse for gears, bushings, and other moving parts. Nylon absorbs moisture, though, which can affect dimensions in wet washdown environments. That’s something our engineers plan for during mold design.

Is ABS food safe? It depends on the grade. Many general-purpose ABS formulations aren’t intended for food contact, but specific compliant grades are available. ABS is often a great choice for housings and non-contact components where toughness and a clean cosmetic finish matter.

Polypropylene and acetal are also common in food processing. Polypropylene is lightweight and chemically resilient. Acetal brings low friction and strong dimensional stability, which is why it’s popular for conveyor parts and components that move against other surfaces.

For a deeper look at these materials, check out our Plastic Resin 101 guide and our post on injection molded plastic products material selection.

Metal Detectable Plastics: An Extra Layer of Protection

Even the best food grade plastic can break under the wrong conditions. When it does, a plastic fragment is hard to spot. Metal detectable plastics help solve that problem. A ferrous metal powder is compounded into the base resin, so if a piece breaks off, the facility’s existing metal detection equipment can catch it before it reaches the end user.

Metal detectable grades are especially useful for parts that sit directly over the product stream, like scrapers, guides, and scoops. Keep in mind that different additives work with different base resins, so not every material is available in a detectable version. We cover this in more detail in our post on metal detectable plastics applications.

Designing Food Grade Plastic Parts That Survive Washdown

Picking a compliant resin is only half the battle. The part also has to hold up to the cleaning routine it will face every single day. A few design considerations to keep in mind:

• Chemical resistance: Sanitizers, caustic cleaners, and hot water can cause some resins to crack, craze, or cloud over time.
• Heat exposure: Hot water and steam cleaning can push some materials past their comfort zone.
• Cleanability: Tight crevices, sharp inside corners, and rough textures give residue a place to hide. Generous radii and smooth surfaces make parts easier to clean.
• Visibility: Many food processors prefer blue parts because blue stands out against most food products, making stray fragments easier to spot.

This is where early design review pays off. Our DFM guidelines cover wall thickness, draft, and other details that affect both moldability and cleanability.

Why Documentation Matters as Much as the Material

With food grade plastic, you need more than the right resin. You need proof. Before production starts, confirm that your molder can provide:

• Resin supplier compliance documentation showing the material meets the FDA or NSF requirements your application calls for.
• Material traceability so you know exactly which resin lot went into which parts.
• A clear regrind policy. At Metro Plastics, regrind material only goes into non-critical parts where virgin resin isn’t required, but it’s always worth confirming how your molder handles it for food-contact components.

Quality systems back all of this up. Metro Plastics is ISO 9001:2015 certified, which means our quality management system goes through annual audits. Our on-site Metrology Lab supports PPAP/FAI documentation and gives real-time dimensional feedback from first article to full production.

Ready to talk through your project? Contact Metro Plastics today to schedule a conversation with our engineering team.