Do meats loose any nutritional value if they are cooked in advance, say sometimes up to a couple days, then refrigerated and eaten?? For work meals i often cook up a ton of chicken breasts that will last me a few days. Oh also another thing, those plain frozen chicken breasts you get in a bag are pretty much the same nutritional value as one you'd get from the butcher fresh right?? I usually buy the 5kg bags from Costco.