Sustainable enjoyment: Food packaging with a barrier layer ensures a longer shelf life

As packaging materials, glass and aluminum inherently have very good barrier properties – they protect the filled content extremely well, and both materials can also be recycled for a very long time. Recycling rates are very high, at least in Europe, thanks to a long tradition of waste separation. This is a plus when choosing the right packaging material. Yet in addition to all the positive aspects, there are also critical aspects to glass and aluminum: glass is fragile and heavy and therefore causes a large amount of CO_2e emissions during transportation. A lot of energy has to be used for production, which also has an impact on the ecological footprint. Aluminum also requires a lot of energy to produce, and the raw materials needed are often associated with the deforestation of primeval forests and rainforests.¹ And plastic? Although it is by no means perfect in terms of sustainability, there are more and more approaches that could make a circular economy a reality in the future. In addition, plastic is virtually unbreakable, lightweight, easy to transport, and it offers very good product protection, especially when combined with barrier technologies. For example, it is possible to embed a barrier layer such as EVOH in a standard plastic – even if the recyclability of the packaging must be taken into account.

But what exactly is the barrier layer designed to protect against? Essentially, there are three different areas:  

• Oxygen can affect the product. The barrier reduces oxygen migration to a minimum. 

• Loss of aroma affects the taste and hence consumer satisfaction – an effective barrier provides a solution to this. 

• A barrier against light: dark materials are applied in the form of layers, in butter tubs for example, to protect susceptible products from UV radiation. 

The barrier therefore ensures a longer shelf life, which often makes preservatives superfluous. Yet what is the ideal type of packaging and what material is it made from? According to Florian Aschermayer, Global Senior Expert Sustainable Material Excellence at Greiner Packaging, there is no easy answer: “It always depends on what I want to achieve – that is, what objective I am pursuing with my packaging. I use different packaging for food that is stored in a cool place and only has a shelf life of two or three weeks anyway than I do for food that is stored at room temperature and needs to stay fresh for months. Better protection is needed in this case, which can be achieved with a barrier layer, for example.” Some products are also particularly sensitive to oxygen or light and often lose their aroma after a short time – barrier packaging can also help in these situations. “However, the choice of the right packaging material and the corresponding barrier solution must always be made in consultation with our customers. There is no one-size-fits-all solution for all foods, as requirements and applications are simply far too different,” Aschermayer stresses.  

There are already plenty of examples of barrier packaging on the market: sauces and dressings in particular benefit from the long shelf life without the need for preservatives. However, pet food producers also rely on plastic barrier solutions. They are also used in ready-made meals and baby food.

What about the environmental footprint of barrier packaging? It’s true that some material combinations of barrier and standard plastic impair the recyclability of packaging, with the best results being achieved by a packaging solution made of mono-material. In many areas, however, the recyclability of packaging is still rated as high if the barrier meets the required criteria, offering additional scope for sustainable barrier solutions. And as already mentioned, recyclability is not the only important factor when it comes to sustainability. Weight also has a major influence on the carbon footprint and transportation costs. This is where plastic with barrier technology really comes into its own. Combined with the high level of convenience for consumers and the excellent differentiation at the point of sale, there is a lot to be said for the use of plastic packaging. After all, packaging makes a significant contribution to extending the shelf life of food, thus minimizing the amount of spoiled food.

¹ https://www.co2online.de/klima-schuetzen/nachhaltiger-konsum/vergleich-umweltfreundliche-verpackungen/#c71936