Consumers nowadays do not have any technology to accurately assess the freshness of fruits, vegetables, and meat in their local supermarkets. As such, we find ourselves squeezing melons, smelling peaches, and looking for the correct color on mangoes. Now German scientists are working on a device that can estimate food freshness using metal oxide sensors.
The system has been developed by researchers at the Fraunhofer Institutes for Molecular Biology and Applied Ecology IME in Schmallenberg and for Physical Measurement Techniques IPM in Freiburg. It checks gas emissions on-line – directly in the warehouse for instance. “We have brought together various technologies based on the use of metal oxide sensors, similar to those installed in cars, for example, to close ventilation vents when driving through a tunnel. Researchers at IPM have developed these sensors further. If a gas flows over the sensor, at temperatures of 300 to 400°C, it will burn at the point of contact. The subsequent exchange of electrons changes the electrical conductivity,” explains Dr. Mark Bücking, Head of Department at IME. “Before the gas reaches these sensors, it has to go through a separation column with polymers. Certain substances are already filtered out here.” A prototype of the analysis equipment already exists. Initial tests were promising – the system measures the volatile substances just as sensitively as conventional equipment used in food laboratories.
Press release: Ripe pineapple and delicious pork…