The induction time measured using the Rancimat cannot be used to directly calculate shelf life.
An important reason for this is that the experiments are structured differently. Measurements using the Rancimat are generally made at temperatures between 100 °C and 130 °C. In addition to accelerating the oxidation process, these temperatures can cause side reactions which do not occur when samples are stored under normal conditions. For example, volatile antioxidants may be driven out or antioxidant compounds may form (e.g., Maillard reaction). Furthermore, in measurements with the Rancimat, air is continuously fed through the sample, whereas it is generally stored in closed containers.
Consequently, the induction time determined using the Rancimat only gives an indication which must be correlated with the actual shelf life of a sample using storage tests.