Spices do go off, especially the ones with volatile oils.... once evaporated they taste like sawdust. I've got a fairly old but very small pot of saffron threads however, and that's still going strong despite being a few years old. World record belongs to my mum. The box of Whitworths Dessicated Coconut she kept on the top shelf of her cupboard (until I finally cracked and chucked it in the bin a couple of years ago) was priced '4d'. And for anyone under 45, that means it was bought pre-1971 Whatever was inside that box, it certainly wasn't coconut any more.