Use by Generally, foods that have a
use by date written on the packaging should not be eaten after the specified date. This term is generally applied to foods that may go bad due to physical instability, chemical spoilage, bacterial spoilage, pathogenic spoilage, or other factors that can make the food injurious to health.
Milk,
meat,
fish and eggs are all subject to spoilage. Such foods should be thrown away if past their
use by date or if showing signs of deterioration such as changes in smell or color.
Fruits,
vegetables,
breads and other baked goods can also spoil, but may be less likely to become dangerous. It is important to follow storage and preparation instructions carefully for perishable foods. Some products may require
refrigeration. Others may need to be cooked to particular temperatures. Most U.S. expiration dates are used as guidelines based on normal and expected handling and exposure to temperature. Use prior to the expiration date does not guarantee the safety of a food or drug, and a product is not necessarily dangerous or ineffective after the expiration date. According to the
United States Department of Agriculture, "High-acid canned foods (e.g. tomatoes and fruits) will keep their best quality for 12 to 18 months. Whereas, low-acid canned foods (e.g. meats and vegetables) will keep for two to five years." If formula is stored too long, it may lose its nutritional value. A study conducted by the U.S. Food and Drug Administration covered over 100 drugs, prescription and over-the-counter. The study showed that about 90% of them were safe and effective as long as 15 years past their expiration dates. Joel Davis, a former FDA expiration-date compliance chief, said that with a handful of exceptions - notably
nitroglycerin,
insulin and some liquid antibiotics - most expired drugs are probably effective.
Best before sealing a bag of
hot dog buns displays a best before date of February 29.
Best before or
best by dates appear on a wide range of frozen, dried, tinned and other foods. These dates are advisory and refer to the quality of the product, in contrast with
use by dates, which may indicate that the product may no longer be safe to consume after the specified date. Food kept after the
best before date will not necessarily be harmful, but may begin to lose its optimum flavour and texture. Eggs can be a special case, since they may contain
salmonella which multiplies over time; they should therefore be eaten before the
best before date. In Britain, this is 21 days from when they were laid. In the USA, this is a maximum of 45 days after the eggs are packed. Quality of the eggs will degrade over time, due to a variety of factors. As a result, some prefer to use fresher eggs for eating and eggs a few days old for cooking. Sometimes the packaging process involves using pre-printed labels, making it impractical to write the
best before date in a clearly visible location. In this case, wording like
best before see bottom or
best before see lid might be printed on the label and the date marked in a different location as indicated.
Best if used by Best if used by/before is a date which is commonly found on labels of meat, egg, or
poultry products. The stated date specifies how long the product will be of top quality or taste. The United States
Food and Drug Administration (FDA) reinforces a push by the
food industry to make
Best if used by the normal wording to show the date when a product will keep its best quality until. Although United States federal law does not require product food dating, the
Food Safety and Inspection Service (FSIS) oversees meat, egg, and poultry products where dates are voluntarily put on in a genuine way to follow the rules of the FSIS.
Open dating Open dating is the use of a date stamped on the package of a food product to help determine how long to display the product for sale. This benefits the consumer by ensuring that the product is of best quality when sold. An open date does not supersede a
use-by date, if shown, which should still be followed. Bathroom products and toiletries usually state a time in months from the date the product is opened, by which they should be used. This is often indicated by a
graphic of an open tub, with the number of months written inside (e.g., "12M" means use the product within 12 months of opening). Similarly, some food products say "eat within X days of opening".
Sell by Sell by date is a less ambiguous term for what is often referred to as an "expiration date". Most food is still edible after the expiration date. A product that has passed its shelf life might still be safe, but quality is no longer guaranteed. In most food stores, waste is minimized by using
stock rotation, which involves moving products with the earliest sell by date from the warehouse to the sales area, and then to the front of the shelf, so that most shoppers will pick them up first and thus they are likely to be sold before the end of their shelf life. This is important, as consumers enjoy fresher goods, and furthermore some stores can be fined for selling out of date products; most if not all would have to mark such products down as
wasted, resulting in a financial loss. == Food waste ==