Nitrogen stripping to remove dissolved oxygen from extra virgin olive oil

The stripping treatment of extra virgin olive oil (EVOO) by nitrogen gas to remove dissolved oxygen (DO) was tested immediately after the oil production. Dissolved oxygen was measured before and after stripping, as well as one week later along with chemical analyses with the aim to assess the effects of the stripping treatment on EVOO quality. Stripping gave a great reduction of DO, of ca 50%. Both stripped (SO) and non-stripped (non-SO) oil samples showed a fast DO consumption up to zero in seven days. At this time, the non-SO samples showed significant higher peroxide value probably as a consequence of the initial higher DO concentration that gives a greater formation of free radicals. A slightly lower concentration of total phenols was recorded for SO samples. A slight but significant decrease was recorded for only (E)-hex-2-enal concentration within the volatile compounds.