Assessment of Oxidative Stability for Lipids

A sample is heated, usually at or above 100°C, while air is bubbled through it, and the volatiles created are transferred to a water trap where conductivity is measured (Fig. D2.3.1). The induction period endpoint is determined by the time it takes for the sample to begin a rapid increase in conductivity. The time required for the sample to reach its induction period endpoint is termed the Oil Stability Index (OSI). The Oil Stability Index is Official Method Cd 12b-92 of the American Oil Chemists Society (AOCS, 1996). 

Detergent that leaves no contaminating residue on glassware (e.g., RBS from Pierce, or Micro from International Products) 

Rancimat (Brinkmann holds 3 or 6 sample tubes) or Oxidative Stability 

Instrument (Omnion available from Archer Daniels Midland holds up to 24 sample tubes) 

25 x 200-mm test tubes, with 2-hole stoppers and aeration tubes 

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