Mechanically Processing Cottonseed to Reduce Gossypol and Aflatoxin Levels

Cottonseed is an economical source of protein and is commonly used in balancing livestock rations; however, its use is typically limited by protein level, fat content, gossypol, and the potential for aflatoxin contamination. There are numerous studies in the literature discussing gossypol and aflatoxin toxicities in livestock and processing methods for reducing gossypol levels in cottonseed. However, there is very limited information in the literature within the last 30 years on how aflatoxin is affected by processing. Evaluation studies were conducted to determine if an extrusion process affected gossypol and aflatoxin levels in cottonseed without negatively impacting the nutritional value of the product, and if these reductions were consistent with the literature. Results from the gossypol study showed a 71 to 78% decrease in free gossypol levels due to the extrusion process, which were lower than some reported methods of processing and consistent with others. Results from the aflatoxin studies showed reductions of 50% when the