Which oil to purchase is a personal choice of each buyer.
What criteria should you pay attention to first of all?
Check the manufacturer's country on the package. Spain, as the largest producer (up to 60% of the world turnover), is famous for strict production control and high quality. What is not allowed in Spain is allowed in other countries. There has been a struggle on this issue in the European Union for more than one year. Spanish producers are seeking to establish equal control methods in all EU countries, as well as to indicate the origin of olive oil on the labels. The reason is because other countries with a smaller volume of their own production buy oil from Spain in barrels, add a little of their own and sell it as Italian, Greek etc. There is no governmental standard for olive oil in Russia. Now many Russian manufacturers and retail chains have begun to produce olive oil under their own brands. And since Russian legislation allows inconsistencies with the European code, often such olive oil does not correspond to the type of oil on the label. Often, in bottles under Russian brands inscribed Extra Virgin oil, there is olive oil of the worst properties inside, and sometimes a mixture with vegetable oil.
Extra Virgin olive oil can't be cheap. If you see a very low price on the tag, this should alert you. Also, better check the expiration date on the package.
It is best to buy olive oil in a glass or tin container. The packaging in which the oil is put must be hermetically sealed and not allow sunlight to pass through. Glass bottles for Extra Virgin must necessarily be made of dark glass, because sunlight accelerates the oxidation process, in which the oil gradually loses its useful properties, quality and taste.
One of the most important indicators of the quality of olive oil is its acidity. Each type of oil has its own limits of acidity. For Extra Virgin oil, it should not exceed 0.8%. The absence of an acidity indicator on the package should alert you.