Possibilities of Sustainable Oil Processing

In a world of rapidly increasing demand for oil and dramatically deteriorating environmental conditions, it becomes ever more important to produce more oil under more environmentally friendly conditions. In general, two types of oil processing are relevant, extraction of oil by pressing or using solvents. Pressing is a very environmentally friendly method without pollution of solvent, but from an economical point of view oil yield is a disaster since at least one third of the oil remains in the press cake. To take into account the huge need for vegetable oils, comprehensive extraction of oilseeds is necessary, and one of the most successful ways is extraction using solvents. Depending on the extraction conditions more than 98% of the oil is recovered from oilseed by this process. Therefore, the only way to achieve economical oil processing and at the same time keep sustainability in mind is further improvement of the traditional solvent extraction. Heightened legal regulations as well as economical requirements have motivated the oil-processing industry to develop new promising approaches to reduce pollution from fumes and liquid waste by changing processing conditions. Additionally, the efficiency of the process has become ever better. On the other side, it is difficult and time-consuming to introduce new approaches into the old, established process of oil production. Nevertheless, there are a lot of approaches available showing promise to improve the efficiency and sustainability of oil processing. In most cases the protein-rich residue is used for animal feeding stuff, but often it contains valuable bioactive minor components that merit coextraction. The isolation and utilization of these unused bioactive compounds is another important factor that can increase the efficiency and sustainability of oilseed processing. Much innovative progress has been made in this area over recent decades. The chapter describes different methods of oil processing from the specific perspective of economical and sustainable production. The different steps of the conventional refining process – such as degumming, chemical or physical refining, bleaching and deodorization, but also alternative techniques – are described