Carrot Protects Cucumber

Lidl Switzerland and the Empa Institute are researching a protective cellulose coating for fruit and vegetables. The novel coating is being manufactured from pomace and is to be used in future for Lidl Switzerland products.

The issue of plastic and packaging reduction has occupied Lidl Switzerland for years. Where possible and ecologically sensible, packaging is omitted completely. This is the case, for example, with organic fruits, which are labeled using laser technology. Reducing food waste is also a core concern for Lidl Switzerland. In order to proactively search for new solutions in this area, Lidl Switzerland approached Empa. Together, the research project was initiated shortly afterwards.

Plastic packaging in grocery stores protects fruit and vegetables from spoilage, but also generates considerable amounts of waste. Together with Empa, Lidl Switzerland has now developed a protective cover for fruit and vegetables based on renewable raw materials. For its latest project, Lidl Switzerland chose Empa as a partner because it had decades of research experience with cellulose products at its disposal, the company explains.

Significantly higher durability

In the Empa Cellulose & Wood Materials laboratory, the researchers then spent more than a year working on behalf of Lidl Switzerland to develop a special protective cellulose coating that can be applied to fruits and vegetables. The result: the coated fruits and vegetables stay fresh significantly longer. In tests, for example, the shelf life of bananas was extended by more than a week. This significantly reduces food waste. “The big goal is that such natural coatings can replace a lot of petroleum-based packaging in the future,” says Gustav Nyström, head of the research department.

Production from press residues and residual materials

In the future, so-called pomace in particular will be processed into fibrillated cellulose. Pomace is the solid residue left over after pressing out the juice of fruit, vegetables or plants. Until now, these plant residues have been disposed of in biogas plants or directly in the field; in the future, the protective coating for fresh fruit will be created from these residues, among other things. Depending on the results of the study, the coating will either be sprayed onto the fruit or applied to the produce as a dip and can be easily washed off. Since it is harmless to consumers, it can also be consumed without any problems. The potential of the cellulose coating is far from exhausted: it is possible to add additives such as vitamins or antioxidants.

Use planned throughout Switzerland

In the summer of 2021, the promising preliminary study, which has been ongoing since 2019, could be successfully completed and the main study started. The cellulose layer developed at Empa will be tested and further improved over the next two years together with Lidl Switzerland and a fruit and vegetable supplier. The project is financially supported by the Swiss Agency for Innovation Promotion (Innosuisse). The aim is for the new technology to be used in all of Lidl’s more than 150 stores in Switzerland following the successful main trial. The research project will mark a milestone for Lidl Switzerland in the area of sustainability. Torsten Friedrich, CEO of Lidl Switzerland explains, “Our new coating technology could represent a milestone in our company’s history. With the protective film, we are not only reducing food waste and packaging material on a large scale, but also extending the shelf life of the food at our customers’ homes. Last but not least, with this project we are once again demonstrating our innovative strength and unique dynamism.”