Advances in Environmentally Friendly Polymers for Food Packaging

Although plastics have received significant backlash and criticism in recent years due to their environmental impact, they play a vital role in food packaging. In fact, their versatility, strength and durability make finding a like-for-like alternative incredibly challenging. 

By Ben Smye, head of growth at materials search engine Matmatch 

To develop sustainable food and beverage packaging without compromising performance, food manufacturers should turn to biodegradable and bio-based polymers. But how viable are these greener plastics? 

The food industry is one of the sectors that benefited the most from the developments in plastics in the past century. Just as refrigeration revolutionized preservation of food for consumers, plastic packaging reshaped product possibilities and food distribution. Plastics provided an effective, mass-producible means of extending the shelf life of products by protecting them from oxidation, microbial growth and some damage during transportation.

To this day, thermoplastics are widely used for the majority of food and beverage packaging. This is due to their flexibility, impact resistance, lower molecular weight and, crucially, their ability to be recycled.

However, being recyclable is not enough on its own. Since it has become apparent that plastic is often not being disposed of properly or the infrastructure is not in place to support recycling of all plastics, the need has arisen for other environmentally friendly alternatives.

Several materials such as paper, glass and aluminum have grown in popularity for food packaging in recent years. But as any design engineer knows, simply substituting one material for another is not straightforward — the properties of the original material and its replacement need to be taken into consideration. This has led many food-packaging companies to instead consider biodegradable and compostable polymers, which can exhibit comparable properties to conventional plastics.

The degradation process that a polymer goes through helps to define whether it is biodegradable or compostable. In the case of the former, the polymer decomposes into carbon dioxide, water, inorganic compounds and biomasses in certain controlled environments, such as under high temperatures or when exposed to certain chemicals.

Compostable polymers, on the other hand, are defined much more closely. European standard EN13432 requires that any plastic that’s marked as ‘compostable’ needs to break down under industrial conditions — in temperatures of up to 60 degrees Celsius — in under twelve weeks.

You can read the rest of this article in the Summer Issue of Asia Pacific Baker & Biscuit magazine, which you can access by clicking here.