EU-funded researchers have created a protective film out of dairy byproducts that will lock in freshness without utilizing petroleum. The petrochemical-based protective film currently in use is difficult to recycle and is not biodegradable.
The key ingredient in the new material is whey, a byproduct of cheese-making. The researchers used powdered whey to create a lacquer-like coating that was then applied to the seal of food containers. The whey-based seal is effective in blocking the oxygen and moisture that can cause food to spoil.
The whey-based sealant can easily be dissolved before the recycling process. The researchers believe that their sealant will be ready to replace petroleum-based sealants within two years.
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