Possible Duplicate:
Shelf life of spices
Suppose I grind the mustard + cumin + pepper seeds and keep them covered in a bowl, after how much time should I expect them to lose their flavor?
Authoritative answers with references to some credible sources will be appreciated.
EDIT 1:
The packed powdered/ground spices we get in shops don't taste the same as freshly ground. Hence my question.
EDIT 2:
Info required for spices namely: Cumin, Mustard, pepper. and Garlic/Ginger too.
