Edible Hemp Film Helped Keep Freeze-Dried Berries Fresher in Storage, Study Finds

A study published in Molecules examined whether adding cannabis extract to polysaccharide-based films could better protect freeze-dried raspberries and blueberries during storage. The team produced several versions of the film with different extract levels, then evaluated how the extract changed the film’s physical performance and how well it preserved the fruit over time. The researchers found the extract altered both barrier and mechanical properties of the films. Film elongation ranged from 32.5 ± 8.6% in the no-extract sample (sample 0) to 44.8 ± 8.2% in the 4.0 F sample, indicating the higher-extract film stretched more before breaking. Adding the extract also increased the films’ polyphenol content, rising in step with the amount of extract used. The analysis also showed particularly strong correlations between color indices (L*, a*, b*) and measures of antioxidant activity, suggesting color shifts tracked closely with antioxidant-related changes in the material.

When used to package freeze-dried fruit, the hemp-extract films were linked to reduced degradation of bioactive compounds during storage and lower microbial counts compared with baseline measurements. For stored raspberries, moulds and yeasts decreased after both 2 and 8 weeks across all cases, with the largest reduction reported for the 4.0 F film, where moulds and yeasts dropped from 0.86 to 0.64 log cfu/g. For blueberries, total bacteria counts fell from 2.52 log cfu/g before storage to 2.28 log cfu/g after 8 weeks in the 4.0 F packaging, while mould and yeast levels declined from 0.89 to 0.67 log cfu/g over the same period.

Taken together, the findings suggest polysaccharide films fortified with C. sativa flower extract may offer a functional packaging approach for freeze-dried fruit by improving film performance while helping limit microbial growth and preserve bioactive compounds during longer storage.