Researchers from the Fraunhofer Research Institution for Modular Solid State Technologies in Munich, Germany have developed a sensor film that can be integrated into food packaging to detect spoiled food. The thin film layer changes color in reaction to spoiled food. From the press release:
The sensor film is integrated into the inside of the packaging, where it responds to biogenic amines. Amines are molecules produced when foods – fish and meat foremost among them – decay. They are also responsible for their unpleasant smell. If amines are released into the air within the packaging, the indicator dye on the sensor film reacts with them and changes its color from yellow to blue. “Once a certain concentration range is reached, the color change is clearly visible and assumes the task of warning the consumer,” explains Dr. Anna Hezinger, a scientist at EMFT. This is not only interesting when it comes to identifying foods that have become inedible. Many people are also extremely sensitive to the presence of certain amines. Which makes a warning all the more important for them.
“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,” Hezinger emphasizes. At the same time, the system is very inexpensive. This is important if it is to be used on a broad scale. Other solutions – such as electronic sensors, for instance – would lead to a steep increase in the price of packaged meat. Things that come in direct contact with food products must also meet high standards. “Food safety is ensured by a barrier layer between the sensor film and the product itself. This barrier is only permeable to gaseous amines. The indicator chemicals cannot pass through,” Hezinger explains.
Press release: Rotten meat doesn’t stand a chance…