A new study conducted at the University of Vienna has shown that bioplastic bottles provide the same protection from rancidity as polyethylene terephthalate (PET) bottles, World Biomarket Insights wrote.

The results of the study, led by the Department of Chemistry’s Marc Pignitter, were published in Food Packaging and Shelf Life journal.

The choice of material was important when prolonging the life of bottled cooking oils with a high unsaturated fatty acids content, the March report said.

PET bottles are widely used in the food industry, for example, to package soft drinks and water, due to their material properties and low cost. However, the polymer does not easily biodegrade and remains in nature for up to 2,000 years, according to World Biomarket Insights.

Polylactic acid (PLA) – a thermoplastic compostable biopolymer derived from fermented plant carbohydrates, such as corn or sugarcane – was a potential alternative to PET for bioplastic bottles, the report said.

PLA is widely used as a material in food packaging, such as cups, plates and cutlery.

In the study, the research team in Vienna investigated if bioplastic bottles made of PLA could also be used to store edible oils, World Biomarket Insights wrote.

The effects of different conventional plastic packaging materials, as well as PLA bioplastic, on the oxidation stability and shelf life of sunflower oil were compared. Compounds that were transferred from the bottle materials to the oils were also analysed.

The results of the study showed that, in some cases, bioplastic bottles made from PLA protected sunflower oil from rancidity better than conventional PET, the report said.

In addition, the study found that PLA bottles – unlike PET bottles – did not transfer “unintentionally introduced substances” (NIAS) to the oil.