Reading an article on E&T's website about the development of sensors to tell you whether or not your milk has gone bad (without having to endure the awful smell of a manual nose test) by changing the colour of the plastic cap!
What a wonderful idea! I think this should be applied to all forms of food so a sticker or a patch on the food label changes colour to let you know if it's gone bad or not! Obviously for fresh items a quick inspection will tell you if they've gone rotten but what about tinned or bottled produce when you only know what state the contents are in once you've opened it...
Schrodinger's beans perhaps? ?
