Shelf-stable foods can be safe forever from a foodborne illness standpoint —however, if the shelf-stable food has been on the shelf for an extended period of time, you might not want to eat it because the quality may not be good. In this case, the "best if used by" or “best before” date on the label of the product is an indication whether or not the quality of the food is good. Food quality deals with the taste, texture, and nutritional value of food. For example, freezer burn, rancidity, and food spoilage are all quality-related issues.