Antioxidants in Italian extra-virgin olive oil reduced at six months of storage

That olive oil sitting on your shelf may lose up to 40 percent of its health benefits if it’s been there for six months, according to a recent study.

The study analysed several varieties of extra-virgin olive oil produced from groves in the Italian countryside at production and during storage. After three months of storage, the antioxidant activity in the oils remained unchanged. However, antioxidants decreased by about 40 percent for almost all of the oils after six months.

“The protective role of virgin olive oil is the result of its specific composition including phenolic compounds known to act as antioxidants,” says lead researcher Antonella Baiano of the University of Foggia in Italy. The health benefits of extra-virgin olive oil may include preventing conditions related to coronary disease, stroke and certain types of cancers.

Researchers recommend consumers store extra virgin olive oil in small glass bottles (one litre maximum because the oxygen contained in the headspace determines its oxidation), in a dark location, at a temperature lower than 68-77°F (20-25°C).