Biodiesels jatropha and pongamia synthesized from their respective non-edible seed oils, and PBD (palm biodiesel) synthesized from edible oil were blended with different weight ratios to examine the influence on the OS (oxidation stability). Dependence of the OS on esters of fatty acid composition was also examined. Good correlation between the OS and PAME (palmitic acid methyl ester) was obtained. A correlation between the OS and X (total unsaturated fatty acid methyl ester) was also obtained. Using these correlations. OS of different biodiesel blends can be determined. (C) 2010 Elsevier Ltd. All rights reserved.