Sensitive food needs a high barrier to protect the aromas and hinder the food from going bad. Today, that barrier can be fully recyclable.
Without food packaging, the pile of food waste would grow explosively. Food packaging is necessary to protect the food from external circumstances that might affect the quality of the food, but also to hinder aroma to evaporate from the food.
Sensitive food like spices or other aromatic food that require long shelf life are particularly dependant of high barrier packaging to preserve the food quality.
“Dried food like soups where you have eliminated water altogether is very sensitive to moisture. If the soup powder comes into contact with water not only the taste will deteriorate, but the product might also become mouldy. Fatty products may also get rancid if exposed to oxygen”, explains Jaroslaw Kaczanowski, Strategic Product Development Manager at Walki.
Food with strong aromas such as spices also need a high barrier. “As the spices have an intense aroma, we want to keep the flavours inside the package. Moreover, we do not want the strong flavours to contaminate other products we might have in our kitchen cupboard. We need to protect the food from outside parameters, and make sure that the aroma won’t disappear from the package”.
Keeping properties intact with a high barrier
The better the barrier, the longer the shelf life.
The barrier ensures that the product properties are kept intact from production, through storage and distribution, on the supermarket shelf and finally in the consumers’ cupboard all the way until consumption.
Traditionally in flexible packaging, aluminium foil or high barrier plastic films have provided high barrier features as a part of a multi-material laminate. While this solution does a good job in protecting the food, the multi-material structure poses problems when the package is to be sorted and recycled. No wonder that during the last years, the development to find more sustainable alternatives has been intense.
“The challenge is to develop high barrier properties, but only using one material because these so-called mono-materials are much easier to recycle.”
Dispersion and mdo-pe makes packaging recyclable
The transition from plastics-based packaging to fibre solutions is well underway. However, for food products requiring a high barrier, fibre alone won’t do the trick because paper is a fragile material and sensitive to humidity. You need another material in addition to paper to provide a high barrier.
“At Walki, we coat the paper with a water-based coating that provides a sufficient barrier for oxygen, water vapour and for keeping the aromas intact. Thanks to this dispersion coating technology, the water-based coatings easily pass the repulping process together with the fibres.”
“During the recycling process, the reject ratio of the fibre material is really low, meaning that you get a high fibre yield from the packaging. Different products need different solutions, which is why we apply the coating ourselves in our plants because then we can combine different barriers with the best paper to get the right properties for each product. Not all products need a barrier against both oxygen and water, some only need one of them. It’s a matter of finding a fit-for-purpose solution.”
Another way to provide mono-material high-barrier packaging is to use polyethene (PE) film, also coated with special barrier materials. MDO technology, where you stretch the plastics film very thin, facilitates further coating and improves mechanical and thermal properties of the film compared to regular blown PE films. Such barrier-coated MDO film can be then laminated with another layer of heat-sealable PE, selected according to the product needs.
“While it’s a multilayer structure, as both layers are made of PE, it can be recycled and reused in other products again”.
La elección de una u otra opción para los productos de alta barrera depende de la infraestructura de reciclaje, de las líneas de producción de los productores y transformadores de alimentos, así como de las preferencias de los consumidores.
No obstante, una cosa está clara.
“En el futuro, todos los envases que utilicemos deberán ser reciclables o compostables, e incluso, a ser posible, fabricados con materiales renovables”, concluye Jaroslaw Kaczanowski.