Innovation That Matters

The coating serves the same purpose as a plastic film, by stopping oxygen reaching the food | Photo source Michael Kucharski on Unsplash

Preservative food coating made from passion fruit

Food & Drink

The new material could replace plastic packaging

Spotted: It is estimated that 8-10 per cent of global greenhouse gas emissions are associated with food that is not consumed, and a substantial portion of that waste comes as a result of foods turning bad before they can be eaten. A natural antioxidant, passion fruit peels are an overlooked material that could hold the key to extending the shelf life of food, thus reducing the amount that ends up in landfill. A team of researchers from the University of Johannesburg has recently created a way to use the peels as a healthy preservative for fresh fruits and vegetables.

By microencapsulating the antioxidants in the peels before freeze-drying and grinding the peels into a powder, the scientists produced an organic, edible coating that blocks oxygen from reaching produce while also locking in the food’s naturally occurring moisture. The peels are antimicrobial, an essential factor in healthily preserving fresh cut fruits. And, crucially, the coating also does not interfere with the taste, colour, or general appearance of the produce.

Once used on an item, the antioxidant and antimicrobial qualities ensure that if a package is opened and closed multiple times, the strength of the coating remains intact. This also helps reduce spoilage from food that is not consumed in a single use. If kept in a cool, dark storage space, researchers predict that the powder could last up to six months at full strength.

Improving the way foods can be preserved sustainably would drastically help cut food waste. Springwise has spotted edible packaging made from kelp and seaweed, and another coating solution that is biodegradable and allergen-free.

Written By: Keely Khoury

Website: uj.ac.za

Contact: uj.ac.za/research/contact-us