How many types of materials are used for food packaging bags?

I. Introduction: Core Value and Selection Logic of Food Packaging Bag Materials

• Core Significance: Materials directly determine the shelf life, safety and packaging texture of food.
• User Pain Points: Unable to distinguish material differences, ignoring safety standards, and improper selection leading to food spoilage.
• Core of This Article: Cover mainstream material types, combine the latest 2025 standards, and provide actionable selection solutions.

II. Classification, Core Characteristics of Mainstream Food Packaging Bag Materials (with Application Scenarios)

(I) Plastic Materials (Most Widely Used)

• Polyethylene (PE): Including LDPE, HDPE, LLDPE, soft and low-temperature resistant, used for plastic wrap, shopping bags, frozen Food Bags.
• Polypropylene (PP/BOPP): High-temperature resistant (-40~120℃) and high transparency; BOPP is suitable for biscuit packaging, and PP can be used for microwave heating bags.
• Polyester (PET/BOPET): High mechanical strength and excellent aroma retention, used for Retort Pouches, beverage bottle labels and composite substrates.
• Nylon (PA/BOPA): Oil-resistant, puncture-resistant and good oxygen barrier property, suitable for oil-based products, vacuum packaging and heavy-duty frozen Food Packaging.
• PVC: High transparency but contains plasticizers, rarely used for direct food contact packaging now.
• Special Plastics: Segmented materials such as KOP (moisture-proof and airtight), matte OPP (decorative), POPP (light-shielding pearlescent), etc.

(II) Paper Materials (Eco-Friendly Adaptable)

• Ordinary Paper: Kraft paper (tear-resistant, used for bread and nut bags), white cardboard (excellent printability, suitable for biscuit boxes).
• Functional Paper: Laminated paper (PE coating, moisture-proof, used for hamburger paper and cake trays), cellophane (biodegradable, preferred for traditional candy packaging).

(III) Composite Materials (High-Performance Requirements)

• Aluminum Foil Composite: Optimal barrier property, suitable for high-end fresh-keeping packaging such as coffee and milk powder, needs to be used in composite with plastic/paper.
• Aluminized Composite: Lower cost than aluminum foil, light and oxygen barrier, used for potato chips and Snack Packaging.
• Multi-Layer Co-Extruded Film: Customizable performance on demand, suitable for liquid food and vacuum packaging.

(IV) Biodegradable Materials (Eco-Friendly Trend)

• PLA (Polylactic Acid): Made from corn starch, biodegradable, used for disposable Food Bags and tableware.
• PBAT/Starch-Based Materials: Good flexibility, blended with PLA to make eco-friendly packaging bags.

III. Safety Standards for Food Packaging Bag Materials (2025 Updated GB4806 Series)

• Core Requirements: Compliant raw materials, up-to-standard harmful substance migration, complete labeling (must indicate "for food contact" and temperature range).
• 2025 Update Highlights: New control over coatings and silicone rubber, clarifying dual responsible subjects of production and use.
• International Standards Reference: EU (EC) No. 1935/2004, US FDA, German LFGB regulations.

IV. Selection Skills for Food Packaging Bag Materials (Adapted to Food Types)

• Frozen Food: Prioritize BOPA/PE composite film and LLDPE, emphasizing low-temperature resistance and puncture resistance.
• High-Temperature Retort Food: Choose BOPET/aluminum foil composite and PP materials, resistant to 240℃ high temperature.
• Oil-Based/High-Protein Food: Nylon and KOP materials, blocking oil and odors.
• Snacks/Candies: BOPP, POPP and cellophane, balancing aesthetics and basic fresh-keeping.

V. Common Misunderstandings and Precautions

• Misunderstanding 1: Biodegradable materials do not require standardized storage (need to be stored in a cool and dry place to avoid premature degradation).
• Misunderstanding 2: Aluminum foil bags can be used alone (no sealing property, need to be combined with other materials).
• Precautions: Avoid microwave heating with PVC bags, and separate composite materials during recycling.

VI. Conclusion: Core Principles of Material Selection