During a production process, a product arises that is unintended, but still has a positive value or is useful. That unintended product is the byproduct. Usually, the byproduct can be used for useful purposes.

Bio-industry

Examples of byproducts are often found in agriculture and in the food industry. For instance, not all meat from a pig can be used in a pig slaughterhouse, and residues like intestines, bones, hair, and blood remain. These residues can be processed into animal meal or used as fertilizer.