Knowing whether food has spoiled without tasting it, is now possible. Smart Tags, developed by Chinese scientists, are small gel-based tabs that stick to containers of food and change color when something has expired.
Presented at a meeting of the American Chemical Society, the labels have been successfully tested on cartons milk.
Made of metallic nanorods, vitamin C, acetic and lactic acids and agar, Smart Tags change color and react to alterations in temperature that may affect food freshness.
Programmed to change color over the expiration cycle of a product, the tabs start red, then switch to different shades of orange, yellow and, when the food goes bad, they become green. It could have been a NANO Supermarket product!
Source: CBS News