If you found some mould on a slice of bread - would you eat it, cut it off, or throw the loaf away? What exactly is that green fur anyway? In this episode we’re asking whether we’ve become overly cautious about rot, and finding out how our attitudes to decaying food have changed. The BBC's Emily Thomas talks to Chris Wells from Leatherhead Food Research to find out when old food really becomes bad for you. Food historian Helen Zeit from Michigan State University explains how we may have become less tolerant of older food, and Christina Rice of Harvard law and Policy Clinic explains why the consumer is so confused over when to throw food away. Of course many of us are prepared to put our reservations about old food on hold when something’s presented as a delicacy. We’ll meet people who take pride in eating the oldest food they can – from a Sardinian cheese full of jumping maggots to a man who lived off fermented food alone for a year. Finally we’ll get up close to some creatures which you could call the true masters of the decomposing meal. (Photo: Mouldy bread. Credit: Getty Images).