My daughter regularly phones me to say that she's had a packet of mince/chicken or whatever in her fridge, and it "expired" yesterday, and is it ok to eat it. And I say, give it a good sniff, but it's probably fine. After all, there was a time when there were no such things as sell-by dates. Or, come to that, fridges. My kids love to go through our larder crying "MUM! Have you seen he sell-by date on this!?" (No, probably not. Nor do I care. I seem to have mislaid a treasured tin of anchovies dated 1987.)
But yesterday, having cheese and chutney for lunch, I decided that the sell-by date people may occasionally have a point. The chutney (2007 - one of those pretty little jars of home-made stuff people give you when they come for a meal - was horrible (it had been open for some time), and I discovered that the cheese, which also tasted odd, was thick with mould on the bottom (the bit I couldn't see). And when we once borrowed some (open) horseradish sauce from a neighbour, and found that that too tasted very odd (it was also a nasty grey clour), we discovered tha that had a sell-by date of 1997. (The neighbour is a woman after my own heart, but we threw the sauce away.)
But I do hate waste.