The role of oxygen and water in the extra-virgin olive oil process

Oxygen and water play critical roles in the extra virgin olive oil process. Oxidative reactions are essential for the development of positive sensory notes such as grassy and fruity flavours (the LOX pathway). At the same time, excessive oxidation leads to oil spoilage and the formation of sensory defects like rancidity. Similarly, the presence of water is necessary to enzymic reactions that modify the polarity of phenolic compounds allowing them to be transferred into the oil phase. However, excess water in the oil can spur enzymatic or even microbial degradation during the oil storage with irreversible loss of sensory and nutritional quality. A suitable tuning of oxygen and water roles is one of the most important control tools in the extra virgin olive oil process.