Seaweed Coating Extends Strawberry Freshness, Reduces Waste
Researchers develop an edible, agar-based film that keeps fruit fresh for days at room temperature and preserves nutrients.
An innovative edible coating derived from seaweed can significantly extend the shelf life of strawberries, keeping them fresh for at least four days at room temperature, according to researchers at the University of British Columbia. This development has the potential to reduce food spoilage, large-scale food waste, and the reliance on refrigeration.
The coating is created using agar, a substance extracted from red seaweed, which is commonly used as a gelatin alternative and thickening agent. When combined with zinc, an essential nutrient, and tannic acid, a natural plant compound, the agar transforms into tiny microparticles. These particles self-assemble to form a thin, protective layer around the fruit.
Strawberries coated with this solution emerged with a clear, edible film that dried completely. Over a four-day period at room temperature, the coated berries retained more moisture and remained firmer compared to uncoated strawberries. They also preserved higher levels of vitamin C and antioxidants. In contrast, untreated strawberries began to show mold within two days at room temperature, and refrigeration offered only a marginal extension of their shelf life.
For consumers who prefer to remove the coating, most of it can be washed off with tap water in approximately two minutes, the researchers reported in the Journal of Agricultural and Food Chemistry.
