This common milkweed (Fig. 4.5) is native from the Northeast and North Central United States where it grows on roadsides and in undisturbed habitat (Holser, 2003). On the basis of the fatty acid profile, the oil is expected to provide an alternative source to biodiesel production (Adams et al., 1984). Milkweed oil contains more than 6% of palmitoleic acid that is a strong candidate to enhance fuel properties, besides methyl oleate (Knothe, 2008).

Engine performance tests using biodiesel have been analysed by few authors that found appropriate cold weather properties (Holser and Harry-O’Kuru, 2006). Highly unsaturated ester structures oxidise more rapidly than the saturated ones. These oxidative processes lead to degradation of the fuel and reduce its quality.