Researchers at Thammasat University and Chulabhorn Research Institute in Thailand have developed an invisible, edible coating made with cannabidiol (CBD) that extends the freshness of strawberries and can help improve post-harvest life.
CBD has been shown to have antioxidant and antibacterial effects. Previous studies have found that CBD limits the growth of some pathogenic bacteria and fungi, such as those that cause fresh fruits and vegetables to rot.
Researchers combined CBD with a biodegradable polymer already used in drug delivery to produce particles 400 nanometers wide.
They then mixed the more stable nanoparticles, containing 20% CBD by weight, with water and a food additive called sodium alginate.
The strawberries were dipped in the resulting solutions containing different amounts of nanoparticles, then dipped again in a mixture of ascorbic acid and calcium chloride, which transformed the colorless coating into a gel.
To test the preservative capabilities of the coating, the researchers placed untreated and treated strawberries in open plastic containers at refrigeration temperatures.
After 15 days, they found that the CBD-treated strawberries ripened and decayed much more slowly than the untreated ones.
The edible coating maintained the dark red color of the strawberries, improved their antioxidant activity significantly, and provided the greatest antimicrobial protection during the storage period, suggesting that this version may offer the longest shelf life.
With future studies, this new CBD coating could be used to create an antimicrobial, colorless coating for active food packaging.
