Byprodukter

Byprodukter are secondary outputs that accompany the main product in a production process. They arise across many sectors, including agriculture, food processing, forestry, fisheries, and various industries. Typical examples are oilseed press cake, bran and germ from milling, whey from cheese production, spent grains from brewing, fish heads and viscera, sawdust and bark, glycerin from biodiesel, and slag from metal processing. Some byprodukter have established markets and can be used directly or with minimal processing as animal feed, energy sources, raw materials, or chemical feedstocks; others require additional processing.

In regulation and practice, a distinction is made between byprodukter and waste. A substance is considered a byprodukt rather than waste when its further use is foreseen at the time of production, it can be used directly with limited processing, it remains within the industrial production stream, it is produced incidentally to the main product, and its use does not pose greater risk than the main product. If these conditions are not met, the material is treated as waste and subject to waste-management rules. This distinction influences handling, licensing, and environmental compliance.

Valorization of byprodukter supports the circular economy by reducing waste, recovering nutrients and energy, and enabling new value chains. Challenges include variability in quality, contamination risk, logistical costs, and the need for standards and market development. Overall, byprodukter represent an opportunity for more sustainable and resource-efficient production when managed with appropriate safety and regulatory considerations.