Why do we need food packaging and what is it made of?

Imagine you are walking home one late-spring afternoon, drinking your favourite soda from an aluminium can. In your other hand you’re carrying a plastic bag with your ready-made dinner and a bottle of wine. In your pocket you may have a paper-wrapped candy bar.

Pay attention to these details: there are at least four different families of packaging materials in each shopping bag, and behind each one there are years to centuries of research, technology, and innovation.

What is PC4?

Packaging is an important element of most products sold. It is used along the entire value chain and if used correctly, packaging can significantly reduce product losses. The function of food packaging can be summarized in PC4:

1. Protection The question is: how do I keep foods and drinks away from germs?
2. Containment The question is: how do I keep them from spilling, or wasting, or breaking, or leaking?
3. Communication The question is: how can we all have access to foods and drinks coming from various sources, that we want to be fresh and safe?
4. Convenience The question is: where do I put foods/drinks so that I can carry them around?
5. Conservation. The question is: how do I maintain foods or drinks in a way that they will be fresh and safe tomorrow and the day after?

What is food packaging?

Food packaging is the enclosing of food for the purpose of protection from environmental factors that may cause contamination, damage, or decay in the process of transport, storage or selling.

Insufficient protection shortens the food’s shelf-life, fails to maintain freshness and increases product loss.

In addition to preservation, food packaging used for containing the foods provides information about the ingredients and nutritional values of its contents, and provides convenience for customers — such as easy opening.

What materials are used?

Packaging materials come in different shapes and have various functions. It is essential for the packaging material to have a balance between its shape and its function. Selection of the ideal packaging material for a certain type of food depends on the functions that the packaging should serve.

• There are various forms of metal food packaging, such as cans, tubes, containers, films, caps, and closures.
• There are two types of glass packaging most widely used for foods and drinks: narrow-neck bottles and wide-opening jars and pots.
• Wood is used for crates and kitchen tools.
• Paper is usually used for temporary food containment and protection due to its high permeability and inability to be sealed with heat. Paper is sometimes used as a part of multilayer structures.
• Plastics are the most common and most wide-ranging materials used for food packaging.

Food content material

On a similar note, kitchenware material is a food contact material (FCM) that can potentially release chemicals into food. Cooking food and preserving it after cooking can be done on any surface when it becomes very hot, and therefore the surface remains aseptic. However, contact at high temperature may entail two problems :

1. After returning to room temperature, food residues are optimal for microorganisms and animals.
2. At high temperature the contact materials more easily release chemicals into food, for simple physical (i.e. thermodynamic) reasons.

It does not really matter if the contact material is natural or artificial. Even when cooking on a natural stone, we may detect chemicals released from the stone itself, which is made of solid chemicals.

Most people now use anti-adherent kitchenware. This solves the cleaning problem, but does not solve the migration problem.