Building a 'Nano-Brick' Wall Around Fresh Food
Using a "nano-brick" film composed of 70 percent clay, scientists found they could coat existing packaging and keep food fresh and flavorable for longer.Kelly Redinger/Design Pics/Corbis
A group of scientists from Texas A&M University recently announced a development that could put a cap on flat soda and stale crackers.
Using a "nano-brick" film composed 70 percent out of clay (the rest made from various polymer materials), scientists found they could coat existing packaging and keep food fresh and flavorable for longer. The film is less than 100 nanometers thick (much thinner than a human hair) and reportedly was 100 times more oxygen-impermeable than the silicon oxide coatings of existing food packaging.
“This is a new, ‘outside of the box’ technology that gives plastic the superior food preservation properties of glass,” said Jaime Grunlan, Ph.D., who reported the research to a meeting of the American Chemical Society. “It will give consumers tastier, longer-lasting foods and help boost the food packaging industry.”
The nano-bricks utilize montmorillonite clay, an ingredient commonly used to make building bricks. When viewed under a microscope, the nano-brick's structure even resembles bricks and mortar. It's this structure that makes the nano-bricks such a strong reinforcement to existing packaging.
“Others have added clay to polymer to reduce (gas) permeability, but they are thousands of times more permeable than our film,” Grunlan said. “We have the most organized structure — a nano-brick wall — which is the source of this exceptional barrier. This is truly the most oxygen-impermeable film in existence.”
Manufacturers currently use a variety of packaging materials to preserve food and beverages, but these materials often have drawbacks. Silicon oxide, though it provides a barrier to oxygen, still under-performs the nano-bricks when it comes to preserving food. Plastic packaging that uses a thin coating of metal, besides being un-microwaveable, can be unappealing to consumers who want to see their food purchase.
Grunlan also stated the new coating shows promise for use in flexible electronics, scratch-resistant surfaces, tires and sporting goods, potentially helping basketballs and footballs stay better inflated.