Sterilization in pouches

Everything you need to know about sterilization of food packaged in pouches

Sterilization in pouches

The purpose of this article is to inform you about the special features of this plastic container with regard to the production and marketing of gourmet preserves and/or ready-made meals. Of course, we will focus on pasteurization and sterilization processes when using this type of container so that you can decide whether or not it is the right choice for your products.

Flexible containers for canned food and ready-made meals

Pouch is an Anglo-Saxon term that in our language means bag. In general, pouches, also called doypacks or stand-up pouches, are flexible containers with three seals that are characterized by their ability to stand upright on their base.

It is believed that the history of this type of flexible container began with the invention of cellophane in 1900 by Swiss chemist Jacques E. Brandenberger. Cellophane is a transparent and flexible film obtained by regeneration of cellulose and is mainly used as packaging or wrapping.

After 12 years of research, Brandenberger finally succeeded in patenting this natural polymer. That same year, in the United States, cellophane began to be used to wrap candy.

That was the first step in the search for lighter and easier-to-stack containers, allowing more products to be transported at lower cost. And all this was possible thanks to the development of petrochemical industries and the creation of new machinery.

Nowadays, more and more companies are using pouches to package their preserves and ready-made meals, as this type of container offers multiple possibilities and advantages.

Estructura de un doypack o pouche

Types of flexible containers for food

There is a wide variety of flexible containers for food products on the market. There are different models and sizes, ranging from 33 ml to 1.5 liters.

As mentioned above, these containers have three seals, two longitudinal seals on the sides and one on the top. And they are made with:

  • Two layers of plastic film:
    • One layer of polypropylene (PP) which is a thermoplastic polymer suitable for pasteurizing, sterilizing, modified atmosphere packaging (MAP), blast chilling, freezing, etc.
    • And another layer of thermoplastic polyester, usually polyethylene terephthalate (PET).
  • A metal foil, usually made of aluminum.

In addition, we can find pouches with tear-off opening, for single use or with zipper closure, as well as pouches with spout and cap. The spout can be positioned vertically or at a corner. In the case of pouches with spouts, these can have different diameters and the size of the caps can be standard or wider, making them safe for children.

Advantages and disadvantages of doypacks for the production of preserves and ready-made meals

There are many advantages attributed to this innovative packaging within the food sector, such as:

Yes, there are pros but also cons. One of them would be its recycling, which is complicated as it is a multilayer container and also contains other elements such as the zipper closure or caps. It is true that at present there are already 100% recyclable pouches on the market. But it is also true that they have a higher cost per unit.

Another disadvantage is that the product inside the pouches cannot be seen unlike in the case of glass containers. This is an issue that is also being worked on and there are already companies offering semi-translucent doypacks or with transparent sections.

If you still have doubts, please read this article to find out which are the most suitable containers for the production of canned food.

Envase flexible para conservas y platos preparados

Canned food and ready-made meals in flexible containers

You have probably seen, either on the shelves or in the refrigerators of your local stores, that more and more brands are using this type of heat-sealable bags. Some of the foods we usually find are:

  • Salad dressings
  • Infant food
  • Pet food
  • Fruit in small pieces
  • Olives
  • Ready-to-eat prepared dishes, such as pasta with sauce, meatballs in sauce, creams, etc.
  • Stir-fries and sauces
  • Soups
  • Eggs or liquid egg yolks

Many of the products we find packaged in pouches tend to be sterilized, although this is not a general rule.

Remember that a container does not determine the heat treatment to be applied; what does is the food and the objective of the person who prepares it.

Although there are products that can be found at room temperature and have a shelf life of up to 5 years, there are others that are kept in refrigerators and have a shorter shelf life. This is because they are canned food or ready-made meals that have been pasteurized.

5 steps to create your own preserved food business