Soapstock and deodorizer distillates from North American vegetable oils: Review on their characterization, extraction and utilization

Soapstock and deodorizer distillates are the major by-products from vegetable oil refining. They have little commercial value and are sold at a fraction of the oil cost. However, their characterization reveals the presence of numerous types of compounds, which could be extremely valuable if extracted at low cost. The literature in this area is discontinuous and warrants the effort to produce a comprehensive review. The aim of this review is to combine and condense the body of research performed on these materials, as well as to suggest the best routes for characterization and extraction. Utilization of the components is also discussed.