| Resin identification code | Code 1 — PET or PETE | Code 2 — HDPE |
| Typical appearance | Naturally clear and glossy; can be tinted or made opaque with approved additives. | Usually translucent or opaque with a milky appearance; generally less optically clear than PET. |
| Clarity advantage | Excellent product visibility, making it suitable when customers need to see the food or contents. | Limited visibility can help conceal contents, but it is less suitable when maximum presentation clarity is required. |
| Strength and rigidity | Good stiffness and dimensional stability for clear food tubs, deli containers, and cold-food packaging. | Good toughness, flexibility, and impact resistance; useful for containers that may be squeezed or handled roughly. |
| Common take-out applications | Cold salads, fruit, desserts, bakery items, deli foods, beverages, and display-oriented food containers. | Cold foods, sauces, soups intended for suitable packaging formats, dairy products, condiments, and containers requiring toughness. |
| Moisture barrier | Very good resistance to water and moisture transfer for many food-packaging applications. | Excellent moisture barrier, especially suitable for wet foods and products that must retain moisture. |
| Gas and aroma barrier | Generally provides a stronger barrier to oxygen and carbon dioxide than HDPE, although performance depends on wall thickness and design. | Good moisture barrier but generally more permeable to oxygen and some aromas than PET. |
| Grease and chemical resistance | Good resistance to many food oils and dilute acids; compatibility should be verified for hot, fatty, or highly acidic foods. | Good resistance to many household chemicals, acids, bases, and food ingredients; formulation and temperature still affect performance. |
| Heat-use considerations | Standard PET take-out containers are commonly selected for cold or ambient foods. Do not assume microwave or hot-fill suitability unless the package is specifically designed and labeled for that use. | HDPE can tolerate more impact and temperature variation than many clear plastics, but ordinary containers should not be used for microwave heating or very hot foods unless specifically rated and labeled. |
| Typical food-contact regulatory basis in the United States | PET materials may be covered by FDA food-contact regulations such as 21 CFR §177.1630 when the composition and intended conditions of use meet the applicable requirements. | Polyethylene materials may be covered by FDA food-contact regulations such as 21 CFR §177.1520 when the composition and intended conditions of use meet the applicable requirements. |
| Important FDA compliance point | The recycling code alone does not prove food-contact compliance. The finished article, additives, manufacturing process, food type, temperature, and contact time must be evaluated. | The recycling code alone does not prove food-contact compliance. The finished article, additives, manufacturing process, food type, temperature, and contact time must be evaluated. |
| Recycling profile | Widely collected in many recycling systems, but actual acceptance depends on local collection and sorting infrastructure. | Commonly recyclable where local programs accept rigid HDPE containers; local rules determine actual recyclability. |
| Best choice when... | Clear presentation, product visibility, stiffness, and stronger gas-barrier performance are the main priorities. | Toughness, impact resistance, moisture protection, and resistance to many food ingredients are the main priorities. |