Soon, you’ll be able to get a box of fresh, freshly picked strawberries from your local grocery store or farm. But it is disappointing when you bring them home and find that the ones below are starting to rot. To increase the shelf life of berries, researchers reported on Applied Materials and ACS Interfaces Incorporating cannabidiol – a non-hallucinogenic compound from cannabis known as CBD – and sodium alginate in an edible antimicrobial coating.
CBD is very popular because of its potential therapeutic effects. But this hemp has also been shown to have antioxidant and antimicrobial properties. In previous studies, CBD limited the growth of certain disease-causing bacteria and fungi, such as those that cause rotting fresh fruits and vegetables. However, the oily compound must be evenly distributed in the water before it can be widely incorporated into foods or used to preserve food. One possible way to do this is to encapsulate CBD particles in edible polymers. Therefore, Pongpat Sukhavattanakul, Sarute Ummartyotin, and their colleagues wanted to know whether a food coating made using CBD-infused nanoparticles could enhance the antimicrobial activity and increase the freshness of strawberries.
The researchers encapsulated CBD in poly(D,L-lactide)partner-glycolide), a biodegradable polymer used in drug delivery, producing particles 400 nanometers wide. They mixed the most stable nanoparticles, containing 20% by weight of CBD, with sodium alginate in water. The strawberries were then dipped in solutions containing different amounts of nanoparticles before being dipped again into a mixture of ascorbic acid and calcium chloride to turn the colorless coating into a gel.
Untreated and treated strawberries were then placed in open plastic containers at refrigerator temperature. After 15 days, CBD-treated samples matured and degraded much more slowly than untreated samples, possibly due to reduced microbial growth. The coating with the most CBD-loaded nanoparticles maintains a dark red berry appearance, enhances antioxidant activity the most and displays the greatest antimicrobial protection during storage, indicating that this version will result in the longest shelf life. The researchers say their findings demonstrate how encapsulated CBD can be used to create a colorless antimicrobial coating for active food packaging.