AbstractSoybean oil was hydrogenated using two different palladium‐based catalysts, 5% palladium on carbon (Pd/C) and 10% palladium on alumina (Pd/A), at various ratios in a 4‐L reactor under constant conditions (165°C, 2 bar H2, and 500 rpm stirring rate). Reaction rate, trans isomer formation, selectivity ratios, and melting behaviors of the samples were monitored. Activity of Pd/C was about 10 times higher than that of Pd/A, and the reaction rate showed a strong dependency on the support material. Increases in the concentrations of both Pd catalysts did not have considerable effect on trans formation, which is slightly dependent on support material. Oleate selectivity (S21) for all runs varied between 2.48 and 30.34, and type of support material did not have an effect on selectivity. Melting behaviors of the samples were mainly dependent on reaction rates.