A review article by S. Pinzi and colleagues from the University of Cordoba, Spain mentions that the composition of the following "sustainable" oils can be processed into biodiesel which pass the European EN 14214 and United States ASTM D 6751 02 standards: Calophyllum inophyllum, Azadirachta indica, Terminalia catappa, Madhuca indica, Pongamia pinnata, and Jatropha curcas. However, none of these oils can be considered to be the "ideal" alternative that matches all the main important fuel properties which can give the best diesel engine behavior. According to the authors, a high presence of monounsaturated fatty acids (as oleic and palmitoleic acids), reduced presence of polyunsaturated acids, and controlled saturated acids content are recommended as attributes for a good biodiesel composition. In terms of oxidative stability and cold weather properties, the "best fitting fatty acids" are said to be C18:1 and C16:1 fatty acids. The complete review of the paper appears in a recent issue of the journal, Energy and Fuels (URL above)..