IMDEA Energy’s Advanced Porous Materials Unit has developed an innovative material capable of keeping grapes fresh for up to a month without refrigeration. The breakthrough, recently published in the journal Inorganic Chemistry Frontiers, opens the door to a new generation of safer and more sustainable active packaging for food preservation.

This finding is particularly important in a global context where nearly a third of all food produced is wasted. The possibility of extending the shelf life of fruit and other fresh produce through new packaging could significantly reduce losses throughout the food chain.

The material, called IEF-32 (IEF = IMDEA Energy Frameworks), belongs to a family of compounds known as metal-organic frameworks (MOFs), which were recently awarded the 2025 Nobel Prize in Chemistry. IEF-32 is created from calcium, an abundant and biocompatible element, combined with an organic molecule with phosphonate groups and antifungal properties. The result is an orderly, stable and safe structure that acts directly against the fungi responsible for fruit spoilage.

During the study, grapes treated with this material maintained their appearance, firmness and colour for almost 30 days at room temperature and high humidity, conditions in which they would normally spoil within a few days. In comparison, untreated grapes quickly showed spots, mould and clear signs of decay.

Unlike other systems that rely on the release of preservatives, IEF-32 acts directly from its surface, thanks to the presence of acid groups with intrinsic antifungal activity. In addition, the material showed excellent stability and biosafety, proving that it is not toxic to human intestinal and lung cells, which reinforces its potential in real food applications. Although there is still some way to go, the study demonstrates for the first time that phosphonate-based MOFs can be used in active packaging to extend the shelf life of fruit, opening up a new avenue for functional materials that help reduce food waste in a sustainable way.