On the role of squalene in olive oil stability

The role of squalene in olive oil stability was studied for various concent rations and experimental conditions. No effect was found in induction perio ds of olive oil at elevated temperatures using the Rancimat apparatus. Samp les were then stored at 40 and 62 degrees C in the dark, and the extent of oxidation was followed by periodic measurements of peroxide value and conju gated dienes. A concentration dependent moderate antioxidant activity was e videnced which was stronger in the case of olive oil compared to that found for sunflower oil and lard. In the presence of alpha-tocopherol (100 mg/kg ) and caffeic acid (10 mg/kg) the contribution of squalene (7000 mg/kg) was not significant. No radical scavenging activity was observed using DPPH. i n 2-propanol. The weak antioxidant activity of squalene in olive oil may be explained by competitive oxidation of the different lipids present which l eads to a reduction of the oxidation rate. Squalene plays a rather confined role in olive oil stability even at low temperatures.