Olive Oil Glossary

A plain-English guide to 52 olive oil terms, from free acidity and early harvest to oleocanthal and HPLC. Each definition is short enough to quote and links to the Pomoni guide that covers the topic in depth. Grade limits follow the International Olive Council standard and EU rules.

Grades and labels How olive oil is made Taste and freshness Testing and lab terms Compounds and nutrition Origin and Greek terms

Grades and labels

Extra virgin olive oil (EVOO): The top grade of olive oil. It is made only by mechanical means, with no heat treatment or solvents, and must pass both chemical limits (including free acidity of no more than 0.8%) and a tasting panel that finds no defects and some fruitiness. How to evaluate the “extra virgin” claim →
Virgin olive oil: The grade below extra virgin. It is also mechanically extracted, but may have free acidity up to 2.0% and slight sensory defects. How to buy authentic extra virgin olive oil →
Lampante olive oil: Virgin oil with high acidity or clear defects. It is not fit to eat as it is and must be refined first. The name comes from its old use as lamp fuel. How olive oil is tested for purity →
Refined olive oil: Oil that has been chemically and physically treated to remove defects, color and flavor. Refining also removes most polyphenols. Green vs regular olive oil →
“Pure” and “light” olive oil: Retail names for the grade sold simply as “olive oil”: mostly refined oil with some virgin oil added. “Light” describes the mild flavor and pale color, not fewer calories. How to read an olive oil label →
Olive pomace oil: Oil extracted with solvents from pomace, the paste left after pressing, and then refined. It cannot be sold as olive oil without the word “pomace”. The olive oil fraud problem →
Harvest date: The month or season the olives were picked and milled. It is the clearest guide to an oil’s age, because polyphenols and flavor fade from milling day on. Harvest date vs best-by date →
Best-by date: A date set by the bottler, usually counted from bottling rather than harvest, so it does not show how old the oil is. Harvest date vs best-by date →
Lot or batch number: A code that ties a bottle to one production run and its lab results. Every bottle of Pomoni oil carries its harvest date and batch number. The olive oil label checklist →
Single-origin olive oil: Oil from one named source (a country, region, estate or grove) rather than a blend of oils from different places. Pomoni’s oil comes from a single grove in Messinia, Greece, and is never blended. Single-origin vs blended olive oil →

How olive oil is made

Early harvest: Olives picked while still green or just turning color, in Greece usually October and early November. Early-harvest oil yields less per tree but is greener, more bitter and peppery, and higher in polyphenols. What “early harvest” means on a label →
Cold extraction (cold pressed): Under EU rules, “cold extraction” and “first cold pressing” may only describe oil made below 27 °C. Lower temperatures help keep aroma and polyphenols. Pomoni’s oil is cold-extracted at 23 °C. Cold-pressed vs regular olive oil →
Malaxation: The slow mixing of crushed olive paste so that tiny oil droplets join together and separate more easily. Its time and temperature affect both aroma and polyphenol content. The milling process at Pomoni →
Decanter (centrifuge): The machine most modern mills use to separate oil from the olive paste by spinning it. “Two-phase” decanters add little or no water, which helps keep more polyphenols in the oil. How olive oil is still made in Greece →
Pomace: The solid paste of skins, pulp, pits and water left after the oil is separated. It is used for pomace oil, fuel or compost. How olive oil is produced in Greece →
Filtered and unfiltered oil: Filtered oil has had fine olive particles and water removed. Unfiltered oil looks cloudy and tastes fresh at first, but the sediment can make it spoil sooner. Filtered vs unfiltered olive oil →
Cultivar: The variety of olive tree, such as Koroneiki, Picual or Arbequina. The cultivar shapes flavor and how many polyphenols an oil can reach. Koroneiki olive oil →

Taste and freshness

Fruity: The fresh aroma of sound olives, green or ripe, sensed through the nose. Extra virgin oil must show some fruitiness on a tasting panel. How to taste olive oil like a professional →
Bitter: A positive tasting attribute, felt on the tongue, that comes mainly from polyphenols. It is strongest in early-harvest oil. Why bitterness and peppery burn mean quality →
Pungent (peppery): The peppery catch at the back of the throat, sometimes enough to make you cough. It is linked mainly to oleocanthal. Why green olive oil has a peppery kick →
Sensory defects: Faults found by a trained tasting panel, such as rancid, fusty, musty or winey-vinegary. Any defect rules an oil out of the extra virgin grade. What real olive oil should smell and taste like →
Rancid: The stale smell and taste of oxidized oil, often compared to old nuts, crayons or putty. Heat, light, air and time cause it. Signs your olive oil is rancid →
Oxidation: The reaction between oil and oxygen that slowly breaks down flavor and polyphenols. Dark glass, a cool cupboard and a tight cap slow it down. How to store olive oil →
Smoke point: The temperature at which an oil starts to smoke. For cooking, how well an oil resists oxidation matters more than its smoke point, and extra virgin olive oil holds up well. Can you fry with extra virgin olive oil? →

Testing and lab terms

Free acidity: The share of free fatty acids in the oil, expressed as a percentage of oleic acid. It is a chemical marker of fruit and processing quality, not something you can taste. Extra virgin oil must be 0.8% or lower. Acidity levels explained →
Peroxide value: A lab measure of early oxidation, in milliequivalents of oxygen per kilogram. Extra virgin oil must be at or below 20. How olive oil is tested →
UV absorbance (K232, K270): Readings of how the oil absorbs ultraviolet light. They reveal oxidation and can show whether refined oil has been mixed in. How olive oil is tested for purity →
Panel test (organoleptic assessment): The official tasting method, in which a trained panel scores an oil’s fruitiness and defects under International Olive Council rules. The grade depends on it as much as on the chemistry. How to evaluate the “extra virgin” claim →
HPLC: High-performance liquid chromatography. It separates and measures individual phenolic compounds and is the basis of the International Olive Council’s method for olive oil biophenols (COI/T.20/Doc. No 29). Pomoni reports HPLC results only. HPLC vs NMR →
NMR: Nuclear magnetic resonance. Labs use it to measure specific compounds such as oleocanthal and oleacein. NMR and HPLC figures come from different methods, so they should not be compared directly. HPLC vs NMR →
mg/kg: Milligrams per kilogram, the usual unit for polyphenols in olive oil. An oil at 600 mg/kg has about 12 mg of polyphenols in a 20 g serving (about 1.5 tablespoons). How to read a polyphenol lab report →
Certificate of analysis (COA): A lab’s signed report of test results for a specific batch, with the method, date and report number. A polyphenol claim without one is a marketing claim. Pomoni’s lab results →
ISO/IEC 17025: The international accreditation standard for testing laboratories. It shows a lab’s methods and quality system have been independently assessed. Pomoni’s lab results →

Compounds and nutrition

Polyphenols (biophenols): Plant compounds found in extra virgin olive oil but largely removed by refining. Olive oil contains several families, the most studied being the secoiridoids. The science of olive polyphenols →
High-phenolic olive oil: Extra virgin olive oil with an unusually high polyphenol content. There is no legal definition. The term is often used for oils that reach the EU health-claim level, about 250 mg/kg of hydroxytyrosol and its derivatives. High-phenolic olive oil: the complete guide →
Secoiridoids: The main family of olive polyphenols, which includes oleocanthal, oleacein and the aglycones of oleuropein and ligstroside. The science of olive polyphenols →
Oleocanthal: The secoiridoid behind olive oil’s throat sting. In Pomoni’s latest HPLC test it measured 111.9 mg/kg. Oleocanthal →
Oleacein: A secoiridoid closely related to oleocanthal and one of the most abundant polyphenols in fresh early-harvest oil. In Pomoni’s latest HPLC test it measured 92.1 mg/kg. Oleacein →
Oleuropein: The bitter compound in olives and olive leaves. In oil it appears mostly as its aglycone, which breaks down into hydroxytyrosol. Oleuropein →
Hydroxytyrosol: A simple phenol formed from oleuropein. It is the compound named in the EU health claim for olive oil polyphenols. Hydroxytyrosol →
Tyrosol: A simple phenol related to hydroxytyrosol, formed from ligstroside. It is more stable in the oil but less potent as an antioxidant. Tyrosol →
EU olive polyphenol health claim: The claim allowed by EU Regulation 432/2012: “Olive oil polyphenols contribute to the protection of blood lipids from oxidative stress.” It may only be used for oil with at least 5 mg of hydroxytyrosol and its derivatives per 20 g. Hydroxytyrosol and the EU claim →
Oleic acid: The main fatty acid in olive oil, a monounsaturated fat that usually makes up 55% to 83% of its fatty acids. Olive oil vs other oils →
Monounsaturated fat (MUFA): Fat with one double bond in its carbon chain. It is the main fat in olive oil and avocado oil, and it resists oxidation better than polyunsaturated fat. Olive oil vs other oils →
Olive leaf extract: A concentrated extract of olive leaves, rich in oleuropein. It is one of the three ingredients in Phenolia capsules. Olive leaf extract →
Greek Mountain Tea (Sideritis): Herbal tea from Sideritis plants that grow on Greek mountains, known in Greece as τσάι του βουνού. Sideritis scardica is one of the three ingredients in Phenolia. Greek Mountain Tea →

Origin and Greek terms

Koroneiki: A small-fruited Greek olive cultivar, grown widely in the Peloponnese and Crete, known for high polyphenol potential. Pomoni’s oil is 100% Koroneiki. Koroneiki olive oil →
PDO and PGI: EU origin labels. Protected Designation of Origin (PDO) means every step happens in the named area. Protected Geographical Indication (PGI) requires at least one step there. Both describe origin, not freshness or polyphenols. What PDO and PGI mean →
Messinia: A region in the southwest Peloponnese, Greece, known for olive growing, with Kalamata as its capital. Pomoni’s grove is in Ariochori, Messinia. Climate and soil in Greek olive oil →
Agourelaio: Greek for oil from unripe olives (αγουρέλαιο), the traditional name for green, early-harvest oil. What “early harvest” means →
Mediterranean diet: The traditional eating pattern of olive-growing regions: vegetables, legumes, whole grains, fish, and extra virgin olive oil as the main fat. Why olive oil is a cornerstone of the Mediterranean diet →
PREDIMED: A large Spanish trial that compared a Mediterranean diet supplemented with extra virgin olive oil or nuts against a reduced-fat control diet. What PREDIMED really proved →

Sources

European Commission. Delegated Regulation (EU) 2022/2104 on marketing standards for olive oil. 2022. eur-lex.europa.eu
International Olive Council. Trade standard applying to olive oils and olive pomace oils, COI/T.15/NC No 3. internationaloliveoil.org
European Commission. Regulation (EU) No 432/2012 establishing a list of permitted health claims. 2012. eur-lex.europa.eu
International Olive Council. Determination of biophenols in olive oils by HPLC, COI/T.20/Doc. No 29. internationaloliveoil.org
Pomoni. Lab results and testing. pomoni.com

Last checked October 2026. Spotted a term we should add? Tell us.