The Cambridge economist Piero Sraffa returned to the classical economic meaning of surplus, but his concept differs from Marx's in at least three important ways: (1) The substance of Sraffa's surplus is not a claim on the surplus labour of others but a physical surplus, i.e. the value of physical output less the value of physical inputs used up to produce it, in abstraction from price changes (roughly, like a standard valuation in national accounts); (2) The magnitude of the surplus in ...
, Dream Maker (2009-present) How long does mayonnaise last? How long does Miracle Whip last? Unopened mayonnaise will last at least a week beyond a best by date, erring on the safe side. The shelf life of mayonnaise regardless of such things as the sell by date, use by date, or best before date is not very long.
Due to new packaging methods that extend shelf life, unopened pre-packaged deli meats remain good to eat longer than they did in the past. They may be consumed up to the use by date. Unopened deli meats generally keep for two weeks. However, once the package is opened, the use by date is meaningless; the meat should be consumed within 3-5 days. This is because anti-oxidative gases that preserve pre-packaged deli meats escape from the packaging once it is opened. Unopened packaged deli meat can be frozen for one to two months.