Food packaging materials — explained by a 16-year converter.
Honest deep-dives into the films, foils, and papers we run every day. Written for buyers who want to spec the right material, not be sold a particular stack. Authored by PINHUI's founder Joyce Zhou.
8 materials guides published.
Aluminum Foil — The Only Zero-Permeability Food Packaging Material
Aluminum foil is the only commercially available food packaging material with literally zero gas permeability. For chocolate bars, retort pouches, and any product where 24-month aroma retention is the buying signal, foil is the only material that physically holds up. Here's how to spec it.
Biodegradable & Compostable Laminates — What Actually Decomposes, and Where
The word 'biodegradable' is unregulated almost everywhere. 'Compostable' has meaning only with a specific certification body and a specific composting facility. Here's how the actual materials behave, which certifications you can rely on, and which packaging claims you should never let on your label.
BOPP Film — Biaxially Oriented Polypropylene for Food Packaging
BOPP is the workhorse outer film of flexible food packaging — clear, glossy, dimensionally stable, and three times cheaper than PET. But it cannot heat-seal to itself and its barrier is modest. Here's when to specify it, and when to reach for something else.
Composite Films — High-Barrier Plastic Alternatives to Aluminum Foil
For decades, aluminum foil was the only material that delivered true high-barrier performance in flexible packaging. That's no longer true. EVOH, nylon, and SiOx-coated films now achieve barrier values close enough to foil for most applications — with significant gains in clarity, microwave-safety, recyclability, and cost. Here's how each works and when to spec which.
Kraft Paper — The Heritage Substrate Modern Sustainability Wants Back
Kraft paper is the visual cue buyers have come to associate with 'artisanal', 'natural', and 'sustainable' — but raw kraft alone leaks aroma, wicks oil, and absorbs moisture in days. The version that actually ships in food packaging is a hybrid: kraft outer + PLA inner + optional foil. Here's how each variant works.
PE Film — The Sealant Layer Nobody Sees, and the Mono-Material Future
Polyethylene is the invisible inner ply of almost every flexible food pouch on a supermarket shelf — the layer that actually does the heat-sealing while BOPP or PET gets the print credit. It's also the foundation of the recyclable mono-material packaging movement, which is rewriting the spec sheet for the next decade.
PET Film — Polyester for Heat-Resistant and Premium Food Packaging
PET (polyester) is the second-most-common outer film in flexible food packaging — stiffer, stronger, and far more heat-resistant than BOPP, but 40–60% more expensive per square meter. It's what makes retort pouches survive 121°C sterilization and what gives premium pouches their crisp, structured silhouette.
Metallized PET (VMPET) — The 40-Nanometer Aluminum Layer That Replaces Foil
VMPET is PET film with a vacuum-deposited aluminum coating roughly 30–40 nanometers thick — about 1/200th the thickness of food-grade aluminum foil. It costs 40–50% less per square meter than foil laminate while delivering 90% of the barrier performance. For most flexible food packaging that doesn't need true zero permeability, it's the right answer.