If you have kept some food for a little while, you may not know whether or not is has gone off. Eating it could risk you getting ill, or throwing it away just adds to the food waste mountain.
Researchers have come up with a potential solution. These are smart bio-markers on food packaging which indicate whether or not the food has gone off or is contaminated. Tohid Didar, Professor of Biomedical Engineering at McMaster University in Canada, explains that the technology works by crystals being embedded in the food which can sense contamination, and, when scanned, will indicate to the user if the food is safe to eat.