New Sensor Indicates the State of Your Meat
The sensor film changes color, from yellow to blue. Proof positive that this fish is spoiled.
CREDIT: Fraunhofer EMFT
Many have had the experience; you buy those perfect looking vacuum-packed steaks at the supermarket, only to unwrap them at home and realize the meat had already gone bad while it was still on the shelf. Luckily, the people at Fraunhofer Research Institution have developed a sensor film that changes color to indicate when food has spoiled, so you'll never mistake bad meat for good again.
"Unlike the expiration date, the information on the sensor film is not based on an estimate but on an actual control of the food itself," said Anna Hezinger, a scientist at Fraunhofer.
The sensor strip would be integrated into the inside of the package, so shoppers can just look inside to determine the state of the meat. The strip responds to the molecules that are produced when foods such as fish and meat decay – these molecules are also the ones responsible for the smell that rotting food exudes.
"Once a certain concentration range is reached, the color change is clearly visible and assumes the task of warning the consumer," Hezinger said.
If those molecules – known as amines – are released into the air within the packaging, the sensory film will react, changing color from yellow to blue. Conveniently, the system is also inexpensive, while other solutions such as electronic sensors could cause the price of packaged meat to skyrocket, the sensor strip would not.
Researchers are now working on a measurement module with a built-in sensor film. Employees in the food and packaging industries can use the module to test the freshness of food products directly.