Word is that the dry powder, loses nutritional value, even if refrigerated or kept at freezer temperatures. I don't know how accurate that is, but I try to use it up as soon as I can, and hope that the old batch is finished, at least a few months before I'm ready to purchase the next batch. I buy one each of brewer's yeast and one of BeePro, then shipping is not an extra. It usually arrives in two or three days after it is ordered.