Leftover food containers that auto-detect food contamination
A system of leftover food containers and measurement devices
One solution is a device which measures the amount of harmful bacteria present in food, like this : http://www.foodsafetynews.com/2013/11/personal-handheld-sensors-to-detect-pathogens-could-be-the-future/#.V5ZgxpMrKRs
It is also possible to package leftover food in containers that change their state in some way, if bacteria is present : http://www.food.dtu.dk/english/News/2015/06/Method-provides-more-knowledge-about-harmful-substances-in-food-packaging?id=1fe3b5a0-8c76-4ee5-9fd5-a803878eda4f
It will then be possible to employ a lawyer at the start in order to approve the technological food bacteria detection solutions. This could ensure that leftover food is always fresh enough for consumption.