"Open Dating" is a calendar date applied to a food product by the manufacturer or retailer.
The "Use-By" date is selected by the manufacturer, packer or distributor of the product on the basis of product analysis throughout its shelf life, tests, or other information.
Food spoilage can occur much faster if it is not stored or handled properly.
A change in the color of meat or poultry is not an indicator of spoilage (The Color of Meat and Poultry).
“Closed Dating” is a code that consists of a series of letters and/or numbers applied by manufacturers to identify the date and time of production. Except for infant formula, product dating is not required by Federal regulations.
For meat, poultry, and egg products under the jurisdiction of the Food Safety and Inspection Service (FSIS), dates may be voluntarily applied provided they are labeled in a manner that is truthful and not misleading and in compliance with FSIS regulations.