If you’ve ever had the pleasure of indulging in a box of freshly picked, sweet strawberries from your local grocery store or farm stand, only to find them spoiled a few days later, you’re not alone. To extend the berries’ shelf life, researchers have incorporated cannabidiol (CBD) and sodium alginate into an edible antimicrobial coating.

CBD, a non-hallucinogenic compound from cannabis, is known for its potential therapeutic effects. However, in previous studies, it has been shown to have antioxidant and antimicrobial properties, limiting the growth of some bacteria and pathogenic fungi that cause fresh fruits and vegetables to rot.

Encapsulating CBD molecules in edible polymers is one possible way to distribute the oily compound evenly in water before being widely incorporated into foods or used for food preservation. The researchers tested their theory by producing 400-nm-wide particles made of poly(D,L-lactide-co-glycolide), a biodegradable polymer used in drug delivery, and mixed them with sodium alginate in water. Strawberries were then submerged into solutions containing different amounts of nanoparticles before being dipped 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 temperatures. After 15 days, CBD-treated samples ripened and decayed much more slowly than untreated ones, possibly because of reduced microbial growth. The coating with the most CBD-loaded nanoparticles preserved the berries’ dark red appearance, enhanced their antioxidant activity the most, and exhibited the largest antimicrobial protection over the storage period, suggesting that this version leads to the longest shelf life.

The researchers say that their results demonstrate how encapsulated CBD could be used to create a colorless antimicrobial coating for active food packaging.

The authors acknowledge funding from the Thammasat University Research Unit in Textile and Polymer Chemistry and a Thammasat Postdoctoral Fellowship.

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via EurekAlert!