I have recipes that call for dry roasting peanuts, coconut, and sesame seeds. I make these recipes a lot — so theoretically it would be easier to dry roast everything I have one time, instead of each time I'm making a dish. Would that in any way diminish the taste of the dish? And does the same apply to spices?
Properly stored, dry roasted nuts should lose none of their flavour. Keep them in a well sealed container and they will be fine.
Spices, however, should be freshly toasted, because the point of doing so is to encourage them to release their flavourful oils.