Understanding Can Coatings: Innovations, Regulations, and Health Impacts
Sep 23, 2025
As concerns grow about chemical exposure and environmental safety, the coatings used in food and beverage cans—especially tinplate and aluminum—are under increasing scrutiny. Below is an in-depth examination of the functions, types, alternatives, regulatory landscape, and health implications of modern can coatings—plus insights directly from manufacturers’ perspectives.
Why Are Cans Coated?
Cans serve to preserve flavor, nutrients, and overall quality of food and drink over long storage periods.
To achieve this, coatings must satisfy a variety of technical and food-safety requirements:
Survival during sterilization & heat treatment
Suitability for all kinds of food & beverage matrices (acidic, oily, etc.)
Minimal chemical migration or leaching into food
Strong adhesion—even under deformation
Resistance to aggressive foods (e.g. acids, salts)
Corrosion protection of metal substrate
Maintenance of flavor/texture/appearance over time
Tinplate cans are most often internally and externally coated with thin organic films of 1-10 micrometers before forming. In some cases, acidic fruit cans are uncoated internally, because tin oxidation itself can counter discoloration.
Can Production & Global Market Snapshot
Metric
Value / Estimate
Notes
Annual production of beverage cans (global)
>300 billion units
Includes aluminum + tinplate steel cans.
Steel vs. Aluminum share (beverage cans)
Steel: ~10%, Aluminum: ~90%
Steel includes tinplate and ECCS (electrolytic chromium coated steel).
Food cans globally sold (around 2011)
~75 billion units
Older data but gives scale.
Can coatings market capacity (2011)
~800,000 metric tons
Value approx €2.8 billion at that time.
This scale underlines both the widespread reliance on can coatings and the magnitude of potential regulatory & material shifts.
Types of Coatings & Alternatives
A variety of coating chemistries exist or are under development. Below is a comparison:
Coating Type
Advantages
Limitations / Challenges
Epoxy (BPA-based epoxy-phenolic, etc.)
High stability, strong protection, wide historical usage; excellent adhesion & corrosion protection
Toxicological concerns re: BPA/BADGE; regulatory pressure; may leach unwanted substances.
Acrylic / Polyester
Clean appearance, basic corrosion & stain resistance; used as first-generation alternatives
Less stable under acidic conditions; may be more brittle; higher cost; sometimes less universal performance.
Polyolefin / Non-BPA Epoxy
Emerging options; better safety profile; improved flavor neutrality; corrosion, adhesion & flexibility promising in some cases
Newer tech—may still lag epoxy in certain stress tests; cost and long-term performance under sterilization still being validated.
Vinyl, Phenolic, Oleoresin
Some flexibility; good resistance under certain conditions; possible blends
Poor adhesion at high temp; may alter taste / odor; longer curing times; limited corrosion resistance.
Regulation & Safety: What the Law Requires
USA: Coatings must meet 21 CFR 175.300, which lists permitted substances and limits migration. California’s Proposition 65 requires labeling of BPA use in consumer products.
Europe: Some national laws ban or restrict certain coatings or substances (e.g. BPA, BADGE). EU-wide regulation exists for specific migrants such as bisphenol A diglycidyl ether (BADGE) and inorganic tin. Proposed EU regulation would limit migration of BPA from varnishes/coatings to 0.05 mg/kg food.
Migration, Exposure & Health Impacts
Studies show BPA and its derivatives (BADGE etc.) are the most examined, but many other substances—additives, pigments, lubricants, non-intentionally added substances (NIAS)—also migrate.
Food consumption from cans correlates with measurable BPA exposure in humans; some studies show urine concentrations of BADGE derivatives 3-4× higher than those of BPA in certain contexts.
Toxicological endpoints of BPA include reproductive, developmental, neurological, cardiovascular effects. Some new studies suggest BADGE/BADGE derivatives may also have reprotoxic or developmental effects. Full toxicity profiling for many migrants remains incomplete.
Industry / Manufacturer Perspective & Expert Insights
From the standpoint of tinplate packaging manufacturers, the shift away from traditional epoxy/BPA-based coatings represents both a challenge and an opportunity.
Challenges: alternative coatings often cost more, may require retooling of can processing lines, and often underperform in one or more reliability tests (e.g. extreme acidity, high temperature sterilization, deformation resistance).
Opportunities: growing consumer demand for cleaner labels and safer contact materials; regulatory pressure is forcing transition; brands may benefit in market differentiation by adopting non-BPA or safer coating solutions early. Also, newer coating technologies (non-BPA epoxies, polyolefin dispersions) improve over time, with incremental improvements in scratch resistance, adhesion, and migration profiles.
Best practices recommended by manufacturers include rigorous testing of coating performance under worst-case food matrices; monitoring of NIAS; supplier transparency; and early alignment with upcoming regulatory limits (e.g. EU’s tentative BPA migration limit, or national bans).
Subtitles & Key Takeaways
Epoxy Coatings Still Dominate, But Alternatives Gain Traction
Regulation Tightening: Limits on BPA, BADGE, and Tin Migration
Health Risks Focus: Exposure, NIAS, and Long-Term Effects
Manufacturers Under Pressure to Innovate Without Compromise
“Keyword Table”: Coating Performance Comparison
Keyword
Epoxy (BPA)
Non-BPA Alternatives
Polyolefin Coatings
Adhesion / Deformation Resistance
High
Moderate to High
Improving
Acidic Food Stability
Good
Variable
Promising
Cost per Can
Lower
Higher
Often Higher
Regulatory Risk
High (BPA / BADGE scrutiny)
Moderate
Lower but still evolving
Taste / Odor Influence
Minimal if well formulated
Sometimes more noticeable
Minimal in recent designs
What’s Next: Innovations & Research Trends
Intensified R&D in non-intentionally added substances (NIAS), improving detection, quantification, and risk assessment.
Development of BPA capturing systems and “top coatings” that act as barrier layers to reduce migration.
Growth in polyolefin dispersions and improvements in polyester/acrylic formulations for harsher food conditions.
Increased collaboration between food processors / can manufacturers / coating chemists to co-validate new materials.
Industry Interpretation: From the Manufacturer’s Lens
As a tinplate packaging producer, here's what we are closely monitoring:
Cost vs Compliance Balance: Alternative coatings are costlier but regulatory noncompliance (or consumer backlash) may cost more in recall, brand trust, fines.
Line Adaptation & Process Optimization: New coatings might require different curing temperatures, coatings application techniques, or handling of coils/sheets—equipment investments may be needed.
Supply Chain Transparency: Knowing raw material origins, additive purity, residual monomers or catalysts becomes critical—especially where laws mandate disclosure or migration testing.
Customer Demand & Branding: Brands are asking for non-BPA, clean-label, migration-certified can packaging; early adopters gain marketing advantage.
Have you considered how switching to non-BPA or advanced coating systems could affect your tinplate can manufacturing costs and quality?
If you're a tinplate packaging manufacturer, brand, or R&D professional, contact us to explore coating audit services, supplier evaluation, or pilot testing of next-generation coatings.
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