Just because a food item may be frozen when you buy it, that doesn’t mean it wasn’t thawed and refrozen somewhere along the line. A new self-powered sensor, however, would change color to let you know if that had happened.
Developed by a team from the Istituto Italiano di Tecnologia (Italian Institute of Technology), the food-safe device is currently in functional proof-of-concept form.
It incorporates two electrodes – a magnesium anode and a gold cathode – which are separated by a frozen electrolyte solution. In various versions of the sensor, that solution has contained salts and electrolyte-rich grape, apple and melon matter.
Read more: New Atlas