Identification codes and marks
Identification of a set of units of a product is based on attributing an identifier to the unit of product (batch, lot, etc.) in a form that can be attached to, or conveniently accompany, that unit through, or partly through, an operation or supply chain.
Identification of product units relies upon assigning a unique mark or code based on numbers or alphanumeric strings, including exploiting available standards of identification. In the food supply chain these are invariably open systems where the identification codes adhere to a particular identification convention or standard.
The actual code to be used will depend on business needs and system of traceability to be used. In its simplest from it may just be a unique number or identification reference. An alternative is to encode further data using an alpha-numeric substitution code which may include additional data such as the production site and date, product specification or use by/sell by date.
In order to use an identifier for traceability purposes a data carrier is required. This is a physical thing which is attached to, directly marked on, or accompanies the item, and carries the identification code. Identifiers can be in human or machine readable form.
A range of data carrier technologies are available to support identification of various levels of sophistication. Perhaps the most widely used and recognised in the food industry is the linear barcode.
A barcode is a machine readable representation of data. The data part of a linear barcode comprise a number of alternating dark (bar) and light (space) parallel lines of variable widths. The bars and spaces are structured to carry data in digital form. The rules by which they are structured determine the type of barcode and attributes they exhibit.
Different barcode types have been developed to accommodate numeric or alphanumeric data and reliability in reading. Barcodes are read by optical scanners called barcode readers.