When squeezed, an orange's jets expel a zesty perfume of oil, an attribute prized by chefs and bartenders -- which scientists say could inspire everything from bridge design to drug delivery. Photo by Brandus Dan Lucian/Shutterstock
June 12 (UPI) -- By studying the mechanics of a squeezed orange and its unique multilayered peel, scientists may be able to more accurately predict bridge failures or develop new ways to deliver medicine.
In a new study, published this week in the journal Proceedings of the National Academy of Sciences, scientists at the University of Central Florida characterized the mechanics of an orange peel's miniature jets.
When squeezed, an orange's jets expel a zesty perfume of oil, an attribute prized by chefs and bartenders -- and now, scientists.
"We study natural systems to mathematically characterize how creation works, and despite the ubiquity of citrus-fruit consumption, these jets had not been previously studied," Andrew Dickerson, an assistant professor of engineering at UCF, said in a news release. "Nature is our greatest inspiration for tackling real-world problems."
A hard, shiny outer layer protects the orange. A softer, spongier layer is found beneath. Within the bottom layer are microscopic reservoirs of oil.
When an orange is squeezed, the spongy layer absorbs energy. At a critical threshold, when enough energy has been absorbed, the pressure in the oil reserves causes tiny holes to be ripped open in the outer layer and a jet of oil to be released.
Tiny streams of oil exit the jets at 22 miles per hour, with an accelerating force of 5,000 Gs -- 1,000 times the force astronauts feels as they blast-off from Earth.
"There are several potential applications," said graduate student Nicholas Smith.
Scientists suggest a bridge could deploy a similar mechanism. A bridge could be designed so that when its materials degrade past a critical threshold, a color change is triggered.
"It would have an orange-like skin layer and when you were approaching material failure, you would get a preventative warning," Dickerson said.
The orange peel's mechanics could also inspire new drug delivery methods, the researchers said.
"For asthmatics, you could have a small slice of material which would aerosolize emergency medication that you currently find in expensive, multi-use inhalers," Smith said. "This approach may be less expensive and biodegradable."