The advantage of the product is that it is made of four layers of barrier material, which has high temperature resistance and sterilization characteristics. It is widely used in the food and pharmaceutical industries, ensuring the hygiene and safety of the product and effectively extending its shelf life.
Ø What is a heat-resistant food bag?
A heat-resistant food bag is more accurately defined as a multi-layer material heat-pressed bag suitable for vacuum cooking and high-temperature steaming.
That's a very specific and important term! A food-grade high-temperature retort pouch is a specialized type of packaging designed for commercial sterilization and long-term, shelf-stable food storage.
It goes significantly beyond a typical home-use sous vide or boilable bag.
Here is a breakdown of its structure, temperature capabilities, and primary use:
Ø What is a Retort Pouch?
A retort pouch is a flexible, multi-layered laminate package that combines the advantages of traditional metal cans (shelf stability) and plastic boil-in-bags (lighter weight, better food quality).
The term "retort" refers to the retort processing (or autoclaving) where the filled and sealed pouch is subjected to high heat and pressure to destroy bacteria and achieve commercial sterility.
Ø Temperature & Shelf Life
Process | Typical Temperature | Duration | Key Outcome |
Sterilization (Retorting) | 116°C to 135°C(240°F to 275°F) | 5 to 60 minutes | Kills all microorganisms (like Clostridium botulinum). |
Post-Process Shelf Life | Ambient (Room) Temperature | 1 to 2 years(without refrigeration) | Creates a shelf-stable product (e.g., MREs, canned goods alternative). |
Ø Typical Multi-Layer Structure
Retort pouches require multiple layers to provide strength, heat resistance, and an oxygen/moisture barrier. A common structure for an aluminum-based high-barrier pouch is:
1. Outer Layer: Polyester (PET) or Nylon (PA/BOPA)
Function: Provides mechanical strength, puncture resistance, and is the surface for printing. It has a high melting point.
2. Middle Layer: Aluminum Foil (AL)
Function: This is the critical barrier. It provides near-perfect protection against oxygen, moisture, and light, which is essential for a long shelf life.
3. Inner Layer: Retort-grade Cast Polypropylene (RCPP)
Function: This is the food-contact and sealing layer. It has a high melting point (up to ) and resists corrosion from food acids and oils, allowing the pouch to be heat-sealed and remain stable during the high-temperature retorting process.
Ø Retort Pouch vs. Boil-in-Bag
Feature | Retort Pouch | Boil-in-Bag / Sous Vide Bag |
Main Purpose | Commercial Sterilization (creating a shelf-stable product). | Cooking/Reheating (creating a refrigerated or frozen product). |
Max Process Temp | Up to 135℃(275°F) under pressure. | Max 100°C(212°F) at atmospheric pressure. |
Shelf Life | 1-2 Years (Ambient temperature). | Days to Months (Refrigerated or Frozen). |
Applications | Ready-to-eat meals (MREs), canned meat alternatives, curry, soups. | Sous vide cooking, boiling rice/pasta, reheating prepared meals. |
In short, a retort pouch is the container used by manufacturers to make products like shelf-stable soups or pre-cooked meals.
