This study was performed to optimize and validate Rancimat (Metrohm Ltd., Herisau, Switzerland) operational parameters including temperature, air-flow, sample weight minimize Induction-Time (IT) IT-Coefficient-of-Variation (CV), using Response Surface Methodology (RSM). According a Box–Behnken experimental design, walnut oil equivalent 3-, 6-, or 9-g added each reaction vessel heated 100, 110, ...