Before date is the date to use for eating the food at its best quality or flavor. It is not a purchase date or date of final safety. By date is the last date recommended for the use of a food product. The date has been determined by the manufacturer and indicates the last date for peak quality. Do not use a product after the use by date.
Foods can develop off odors, flavor or appearance due to spoilage bacteria.
If a food has developed any of these characteristics, do not use it, regardless of the date on the package. Mishandling of fresh foods can also change the safe storage time of foods regardless of package dates. Defrosting at room temperature more than 2 hours, leaving foods out of coolers or refrigerators at picnics or parties, taking too long to get refrigerated or frozen foods home and refrigerated after purchase, or using contaminated cutting boards or utensils are other ways of mishandling foods in ways that shorten their safe storage times. Nutrient retention is a key factor in dating of infant formula. If consumed by the use-by date, the formula must contain at least the quantity of each nutrient as described on the label.