Lidl and Swiss scientists develop circular food preservation solution

The new cellulosic bio-coating for fresh produce dramatically reduces both packaging and food waste by coating produce with, well, produce.

the Swiss Federal Laboratory for Materials Science and Technology (Empa) and reseller Switzerland collaborated to develop a protective cellulose coating for fruits and vegetables.

Plastic packaging in grocery stores protects fruits and vegetables from spoilage, but also creates significant amounts of often non-recyclable waste. In collaboration with Lidl Switzerland, Empa researchers have developed a protective cover for fruit and vegetables made from renewable raw materials. If used at scale, the innovation could significantly reduce both packaging and food waste.

In Empa’s Cellulose & Wood Materials laboratory, researchers then spent more than a year developing a special protective coating made of cellulose that can be applied to fruits and vegetables. Result: coated fruits and vegetables stay fresh much longer. In tests, the shelf life of, for example, bananas and cucumbers has been extended by more than a week, which could significantly reduce wastage of fresh produce.

“The big goal is that these bio-based coatings can replace many petroleum-based packaging in the future,” said Gustav NystromHead of the Cellulose and Wood Materials Laboratory at Empa.

Empa’s process takes a substance called pomace – the solid residue left after juicing fruits, vegetables or plants (in this case, carrots) – and turns it into fibrillated cellulose. Previously, this by-product was disposed of in biogas plants or directly in the field; in the future, it can be used to create a protective coating for fresh fruit.

“We have developed a process that allows us to extract the cellulose naturally contained in these vegetables which cannot be sold otherwise”, explains Nyström.

The coating is either sprayed on the fruit or applied to the produce as a dip and is easy to wash off, although it is safe to eat. The potential of cellulosic coatings is still being explored, including, for example, the possibility of adding vitamins or antioxidants. Building on similar food waste reduction solutions offered by companies such as Apeel Sciences — and the growing move by retailers towards reusable, compostable and other circular packaging solutions — Empa/Lidl innovation could help significantly reduce food and single-use packaging waste for the retail detail.

The bottom of these 10-day-old bananas is protected by Empa’s cellulose coating. | Image credit: Manifesto Films/Lidl Switzerland

“Our new coating technology is a milestone in our company’s history,” said
Torsten Friedrich, CEO of Lidl Switzerland. “With this protective film, we will not only make a significant contribution to reducing food waste and packaging materials, but we will also help to extend the expiry dates of food products for our at-home customers.”

France has just become the first country to ban individual plastic packaging for cucumbers and 30 other types of fruit and vegetables. The law has just come into effect, with a complete phase-out of other products by 2026. The government estimates that it will eliminate more than a billion plastic packaging per year.

According to fast business, the researchers concede that plastic probably still protects fruit better: “Plastic creates an almost perfect barrier; and it is difficult to replicate with natural, biodegradable or edible material like we have,” Nyström said. “So it’s not really a fair comparison.”

Still, the solution holds great promise – and as more countries and companies follow France’s lead and ban more and more types of plastic food packaging, solutions such as cellulose liners are expected to be a game changer for food shippers and retailers.

Empa says the cellulose layer will be tested and further improved over the next two years, together with Lidl Switzerland and a fruit and vegetable supplier – with the aim of rolling out the new technology to all 150 Lidl Switzerland stores after the success of the main trial.