Edible films made from dairy and biofuel byproducts
Wednesday 6 June 2007A method developed by Agricultural Research Service (ARS) scientists uses byproducts—not only from dairy processing, but also from biofuel production—to create biodegradable protective films.
The technology was developed by research leader Peggy M. Tomasula and her colleagues at the ARS. They found that combining the milk protein casein with water and glycerol, a byproduct of biofuel production, produces a water-resistant film that can be used as an edible coating for food products.
The scientists used carbon dioxide as an environmentally friendly solvent to isolate dairy proteins from milk, instead of harsh chemicals or acids that can be difficult to dispose of, according to Tomasula. Carbon dioxide (CO2) is another byproduct of the glucose fermentation that is used to make ethanol. Using CO2 makes the edible film more water-resistant and biodegradable.
The resulting food coatings are glossy, transparent and completely edible. Like conventional food packaging, edible films can extend the shelf life of many foods, protect products from damage, prevent exposure to moisture and oxygen and improve appearance. By using renewable resources instead of petrochemicals, the scientists can create more biodegradable products and reduce waste.
Tomasula has been working with a food technologist and a chemist to improve the appearance and protective properties of the casein films.