Flexible Retort Pouch Food Packaging

What this pack is

This retort pouch is built for food that is cooked or sterilised after sealing. The laminate combines three layers: an AlOx PET outer layer, a PA (nylon) middle layer and an RCPP inner layer. AlOx PET is a transparent oxide coating that blocks oxygen and moisture without foil, so the pack can go through high-heat processing while keeping the contents protected. The PA layer adds toughness and puncture resistance, and the RCPP inner layer is formulated to seal and stay intact at retort temperatures.

The structure is designed to withstand up to 135°C for 50 to 55 minutes. That is enough for full sterilisation of low-acid and high-acid foods, giving a shelf life of one to two years without refrigeration. The pouch can be made in any bag type, including flat, stand-up, three-side-seal and spouted formats, depending on how you fill and present the product. Custom colours and print are available.

Heat resistance and material build

The AlOx PET surface layer provides a high barrier against oxygen and water vapour, which helps prevent oxidation and spoilage. It also resists the heat of the retort cycle. The nylon (PA) core gives the pouch strength and toughness, so it resists punctures from handling and from the food itself. The RCPP inner layer is the food-contact sealant; it is chosen because it does not delaminate or lose seal integrity when cooked at 135°C.

Every batch is checked with pressure tests, drop tests, heat resistance tests and seal strength tests. These are routine quality controls for retort packaging, not a claim of a certification held by Clover. The manufacturing partner operates to food-grade standards and the materials comply with FDA and EU food-contact requirements.

Features and options

The pouch can be supplied with a range of closures and features to suit your filling line and end use. Options include spouts and caps, zippers, tear notches, hang holes and carry handles. For retort applications, any fitment must be able to survive the same heat cycle as the pouch itself. Windows can be added if you want to show the product, though a clear window reduces the barrier area. Print methods include rotogravure, digital and flexographic, so you can match brand colours and text.

Because the pouch is sealed and then retort-processed, the closure and seal area are critical. The RCPP layer is designed to seal through contamination and to hold under pressure. The pouch is also built to trap air and retain a clean appearance after cooking, without stratification or deformation.

Where it is used

Retort pouches are used for shelf-stable foods that need a long ambient shelf life. Typical products include sauces, soups, stews, curry, ready meals, meat products, spaghetti sauce, drinks, baby food and fast food. They are also used for pet food and for contract manufacturing runs where the filling line is already set up for retort.

The pouch format can be flat, stand-up or spouted. Spouted pouches are common for liquids and semi-liquids, while flat and stand-up formats suit solid or chunky meals. Because the material is flexible, the pack can be filled on horizontal or vertical form-fill-seal lines, depending on the bag type.

Filling, sealing and handling

Retort pouches are filled, sealed and then processed in a retort vessel. The seal must be strong and complete before the heat cycle begins. The RCPP inner layer is designed to seal at typical retort conditions and to resist delamination. After sealing, the pouch goes through the retort cycle at up to 135°C for 50 to 55 minutes. The pack is then cooled and dried.

The main trade-off with this material is that AlOx PET is not a foil laminate. It gives a good barrier but not the absolute barrier of aluminium foil. For many retort foods that is sufficient, and it avoids the foil layer that can complicate recycling. If you need the highest possible oxygen barrier, a foil-containing structure may be better. For recyclability, mono-material PE and PP options are available, but they may not withstand the same retort conditions. MOQ starts from 100 pcs for pouches with digital printing, or 10,000 pcs with rotogravure. Lead time is 10-15 working days for digital and 20-25 working days for rotogravure after artwork approval. Free stock pouch samples are available; you pay courier only.