December 3, 2023


It may be delicious and healthy, but fruit is also frustratingly fickle and often spoils quickly in the fridge. Now, researchers in Thailand have developed an invisible edible coating made from cannabidiol (CBD) that could keep fruit longer.

We’re all familiar with the disappointment of bringing home a basket of strawberries only to find that the bottom ones are mushy and moldy. In recent years, researchers have used materials made from spider silk, shrimp shells, eggs, pectin or milk proteins to investigate edible coatings that could extend the shelf life of fruit and other perishable foods without compromising their nutritional value or taste— — and now scientists have added CBD to the list.

CBD, a non-psychedelic compound in marijuana, is increasingly used to treat anxiety, epilepsy, pain and other problems. Among its potential benefits, recent research has found signs of antibacterial activity, so scientists at Thailand’s Thammasat University and Chulabhorn Research Institute set out to see if CBD could be used to preserve fruit for longer.

The team combined CBD with a biodegradable polymer already used for drug delivery to make nanoparticles 400 nanometers wide. They are then mixed with water and a food additive called sodium alginate. Next, the researchers dipped the strawberries in the resulting solution, followed by a second dip in ascorbic acid and calcium chloride to turn the coating into a gel.

A comparison of strawberries treated with the new CBD-based coating (left) and untreated strawberries after 15 days in the refrigerator shows differences in spoilage
A comparison of strawberries treated with the new CBD-based coating (left) and untreated strawberries after 15 days in the refrigerator shows differences in spoilage

American Chemical Society

To test the coating’s preservation ability, the team placed treated and untreated strawberries in open plastic containers and kept them at refrigerator temperature for several weeks. Sure enough, the CBD-treated berries took far less time to rot than the naked berries over a 15-day period, and retained their color longer. Higher amounts of CBD also seemed to perform better than lower amounts.

With further research, the new coating could be used to reduce food waste and could be applied to other fruits as well as different types of foods that are prone to spoilage.

The study was published in the journal ACS Applied Materials and Interfaces.

source: American Chemical Society