Two small ceramic bowls of green-gold olive oil beside a sprig of fresh olive branch and a wedge of rustic bread on a linen napkin, a wooden spoon resting across one bowl

Extra Virgin Olive Oil Guide: From Grade to Harvest Date

Published 10 Sep 20266 min read

Extra virgin is a legal grade with numeric thresholds, not a marketing word, and in UC Davis tests of supermarket oils in California, most imported samples labeled extra virgin failed the standard. This guide draws on the International Olive Council trade standard, the EU labeling rules and the research on what reaches a retail bottle. The olive oil buying guide is the long version.

1. What makes an olive oil "extra virgin"?

Two thresholds and a taste test. Under the International Olive Council standard, extra virgin olive oil is obtained from olives solely by mechanical or other physical means, under conditions that do not alter the oil, with no treatment other than washing, decantation, centrifugation and filtration, at free acidity of no more than 0.8 percent, and with a sensory profile of measurable fruitiness and zero defects. In the standard's own table, that means a trained panel's median score for defects must be exactly zero and its median score for fruitiness must be above zero. The panel matters as much as the chemistry: UC Davis summarizes the standard as requiring no rancidity or other off-flavors resulting from poor fruit, processing or storage.

2. What is the difference between extra virgin, virgin, and just "olive oil"?

The IOC standard defines these grades for oil fit for consumption; refined olive oil may be sold direct to consumers only where the country of sale permits it:

Grade	How it is made	Free acidity ceiling	Odor and taste
Extra virgin	Mechanical or physical extraction only, no solvents, no refining	0.8 percent	Panel median of defect 0, median of fruity above 0
Virgin	Mechanical or physical extraction only, no solvents, no refining	2.0 percent	Panel median of defect above 0 and up to 3.5, median of fruity above 0
Refined olive oil	Virgin olive oil refined by methods that do not alter its glyceridic structure	0.3 percent	Acceptable
Olive oil (a blend, no adjective)	Refined olive oil blended with virgin olive oils	1.0 percent	Good
Olive pomace oil	Refined oil from olive pomace, obtained with solvents or other physical treatments, blended with virgin olive oils	1.0 percent for the blended product	Good

The IOC standard also defines ordinary virgin olive oil, at free acidity up to 3.3 percent and sold direct to consumers only where the country of sale permits it, and lampante virgin oil, above 3.3 percent, which is meant for refining or technical use. All the virgin grades come from the fruit alone by mechanical or physical means; refined olive oil, the olive oil blend and olive pomace oil all contain refined oil. Reading the grade name on the front of the bottle is the quickest way to tell which side of that line an oil sits on.

3. What do "cold extraction" and "first cold pressing" mean?

Under EU labeling rules, "cold extraction" may appear only on extra virgin or virgin oil obtained below 27°C by percolation or centrifugation, and "first cold pressing" only on oil obtained below 27°C from a first mechanical pressing in a traditional hydraulic press. Both are optional reserved terms, so a bottle may leave them off. The piece on how olive oil is made at the mill walks through the extraction itself.

4. Which words on an olive oil label are regulated?

The grade names are defined by the IOC standard, and EU rules reserve optional terms around them, including the two cold terms above. Descriptions of taste and smell may appear only on extra virgin or virgin olive oil, and only when they rest on an assessment carried out under the official panel method. UC Davis advises looking for a harvest date rather than the best-by date. Most oil carries no harvest date, it notes, but better producers tend to put it on the package.

5. Is extra virgin olive oil good for you, or is that marketing?

The health claim European regulators have authorized specifically for olive oil rests on its polyphenols. In 2011 the European Food Safety Authority concluded that olive oil polyphenols protect LDL particles from oxidative damage, at a daily intake of 5 mg of hydroxytyrosol and its derivatives in olive oil. Beauchamp and colleagues reported in Nature in 2005 that oleocanthal, a compound whose pungency causes a stinging sensation in the throat, inhibits the same cyclooxygenase enzymes as ibuprofen in laboratory tests, with a potency and profile strikingly similar to ibuprofen's. A 2014 meta-analysis of 32 cohort studies associated higher olive oil intake with lower all-cause mortality, cardiovascular events and stroke. These are findings about the oil's compounds and about long-term diets, not promises attached to any single bottle.

6. Can I cook with extra virgin, and does the smoke point matter?

Yes. In a 2018 laboratory study, De Alzaa, Guillaume and Ravetti heated extra virgin olive oil and other common cooking oils to 240°C and held them at 180°C for six hours. Extra virgin produced the lowest level of polar compounds of the oils tested, with coconut oil close behind. The authors also found that smoke point did not predict how an oil performed under heat. Oxidative stability and UV coefficients, combined with total polyunsaturated fat, were better predictors. Light and heat age an oil faster, so keep the daily bottle away from the burner.

7. What does the harvest date tell me, and why isn't the best-by date enough?

The harvest date is when the olives were picked, which is the clock that matters for freshness. UC Davis advises using extra virgin within 15 to 18 months of harvest and choosing the most recent harvest, and using an opened bottle within a couple of months. Most California and European olive oils are harvested from October to December. Southern Hemisphere oils are mostly harvested from May to July, so they run on a different calendar. On an imported back label, the word may read "raccolta" or "cosecha" with a month and year. For storage, the piece on whether olive oil goes bad is the deep version.

8. How much supermarket "extra virgin" passes the test?

The UC Davis Olive Center's 2010 study tested 14 imported and five California brands sold as extra virgin at retail stores in Sacramento, the San Francisco Bay Area and Los Angeles County. Of those samples, 69 percent of the imported oils failed internationally accepted standards for extra virgin, against 10 percent of the California oils. A 2011 follow-up of 134 samples of eight high-volume brands bought in California supermarkets found that 73 percent of samples from the five top-selling imported brands failed international sensory standards, with defects such as rancidity and fustiness, a fermentation defect. The 2010 release names the likely causes: oxidation from heat, light or age, adulteration with cheaper refined oil, and poor fruit, processing flaws or improper storage. Both studies are snapshots of California retail more than a decade ago; they show why the grade and the harvest date are worth reading, not what any given bottle holds today.

9. Should extra virgin olive oil be bitter and peppery, or is that a defect?

Bitter and peppery are positive attributes in extra virgin, not defects. UC Davis lists fruitiness, bitterness and pungency as the positive attributes of extra virgin olive oil, and the IOC standard requires a panel to find fruitiness in every extra virgin. Pungency is the sting at the back of the throat; the 2005 Nature paper identifies oleocanthal as a compound in newly pressed extra virgin oil whose pungency induces a strong stinging sensation in the throat. How strong those attributes run differs from oil to oil, so two good extra virgins can taste very different. For the tasting method, the olive oil tasting-at-home walkthrough is the kitchen-table version.

10. Is a more expensive bottle better?

The grade test says nothing about price, or about certifications such as DOP or IGP. What a buyer can check on the bottle is the grade and the harvest date. A robust oil and a delicate one do different jobs, so two bottles, each used where it suits, make more sense than one expensive bottle for everything. Capezzana (shop Capezzana) and Graza Sizzle (shop Graza Sizzle) are two extra virgin oils to read that way, alongside other olive oils (shop olive oils).