Extra virgin olive oil is made simply by crushing olives and extracting the juice. It is the only cooking oil that is made without the use of chemicals and industrial refining.
Extra virgin is the highest quality and most expensive olive oil classification. It should have no defects and a flavor of fresh olives.
It must be produced entirely by mechanical means without the use of any solvents, and under temperatures that will not degrade the oil.
Having pleasant spicy fruit flavors characteristic of fresh ripe or green olives.
Ripe fruit yields oils that are milder, aromatic, buttery, and floral.
Green fruit yields oils that are grassy, herbaceous, bitter, and pungent. Fruitiness also varies with the variety of olive.
Creating a mostly pleasant acrid flavor sensation on the tongue.
Creating a peppery sensation in the mouth and throat.
Virgin olive oil has a free acidity expressed as oleic acid of not more than 2 grams per 100 grams and other technical characteristics in the IOC standard.
Ordinary virgin olive oil has a free acidity of not more than 3.3 grams per 100 grams (and the other characteristics for the category).
Virgin olive oil not fit for consumption is designated lampante virgin olive oil. It has acidity of more than 3.3 grams per 100 grams and it is intended for refining or other uses.
Olive oil is the oil consisting of a blend of refined olive oil and virgin olive oils fit for consumption as they are. It has a free acidity of not more than 1 gram per 100 grams and other technical characteristics detailed in the IOC standard.
Refined olive oil is the olive oil obtained from virgin olive oils by refining methods which do not lead to alterations in the initial glyceridic structure. It has a free acidity of not more than 0.3 grams per 100 grams.
Olive-pomace oil is the oil comprising the blend of refined olive-pomace oil and virgin olive oils fit for consumption as they are. It has a free acidity of not more than 1 gram per 100 grams.
Crude olive-pomace oil is olive-pomace oil intended for refining for use for human consumption, or it is intended for technical use.
Refined olive-pomace oil is the oil obtained from crude olive-pomace oil by refining methods which do not lead to alterations in the initial glyceridic structure. It has a free acidity of not more than 0.3 grams per 100 grams and other characteristics in the IOC standard. Olive-pomace oils can never be labelled “olive oil.”
Read more about olive oil grades
Many people don't realize what they are buying when they choose olive pomace oil, only that it has a lower price. In most markets, olive pomace oil use is confined to the foodservice industry.
Olive pomace oil is produced using the same industrial solvents and refining methods used for seed oils such as canola, sunflower and peanut. Still, olive pomace oil is a monounsaturated fat, and is considered a better alternative to polyunsaturated seed oils.
In a widely-cited 2010 report by the University of California at Davis, 69 percent of imported olive oil samples and 10 percent of California olive oil samples labeled as extra virgin found in several supermarkets in California failed to meet the IOC/USDA standards for extra virgin olive oil.