A new, clear, edible food covering, made of casein from cow’s milk mixed with citrus pectin from fruit, blocks oxygen and slows spoilage more effectively than conventional plastic wrappings.
The plastic film was presented by a US Department of Agriculture research team led by Peggy Tomasula at the 252nd National Meeting & Exposition of the American Chemical Society held in Philadelphia last week.
Tomasula and her team started by just using casein protein to form the plastic, but found it was too difficult to handle and easily degraded by water.
Citrus pectin, a type of polysaccharide extracted from citrus fruits, was added to strengthen it. They ended up with a plastic with smaller pores, so allowed less oxygen in than conventional plastics, making it a more effective preserver.
After a few modifications, the plastic looked similar to regular plastic but was less stretchy, a better oxygen blocker and completely edible.
The plan, now, is to apply this technology not just to new wrappings but coatings for food like cereal to keep its crunch instead of the sugar used today.
“The coatings applications for this product are endless,” says Laetitia Bonnaillie, who was involved with the work.
“We are currently testing applications such as single-serve, edible food wrappers. For instance, individually wrapped cheese sticks use a large proportion of plastic – we would like to fix that.”
Future plans also include the addition of vitamins, probiotics and dietary boosters which could eventually be incorporated into the plastic. Flavours could also be added.
The new plastic has only a few drawbacks. It needs a cardboard box or plastic protective bag to keep it sanitary and dry and it’s not ideal for vegans.
Watch the plastic in action below:
Jake Port contributes to the Cosmos explainer series.
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