The relative stability of an expeller expressed, physically refined soybean oil (EE-SBO, iodine value = 126.6) was compared to a low-linolenic acid soybean oil (LL-SBO, iodine value = 120.9) using pan frying. Physicochemical analyses, including free fatty acid analysis, the dielectric constant (Food Oil Sensor), and the Lovibond color were completed. High performance size exclusion chromatography was used to quantify the amount of polymeric triacylglycerol formed in the oil samples during heating. Oil samples were heated as thin films on a teflon-coated frying pan at similar to180C to a target endpoint of greater than or equal to 20% polymer. ne endpoint, as determined by high performance size exclusion chromatography, was reached after 10 min of heating for the EE-SBO (23.8% polymer) and 12 min for the LL-SBO (24.9% polymer) sample. Although the iodine value suggests that LL-SBO should have an oxidative stability comparable to EE-SBO, the results from the physicochemical analyses indicated that the EE-SBO was approximately 20% more stable than the LL-SBO.1115764