Frequently Asked Questions
What is the difference between extra virgin and virgin olive oil?
Extra virgin olive oil (EVOO) is the highest grade, with free fatty acid content ≤ 0.8% and no sensory defects detected by a certified tasting panel. For a complete overview, see our Extra Virgin Olive Oil guide.Virgin olive oil is the next grade down — still unrefined but with free fatty acid content between 0.8% and 2%, or with minor sensory defects detected in the panel test. EVOO retains more polyphenols and has better flavor; virgin olive oil is still edible but has lower quality standards.1
What is refined olive oil?
Refined olive oil is extracted olive oil that has been chemically treated to remove defects (high acidity, off-flavors, oxidation). The result is a neutral-flavored oil with no polyphenols, no aroma, and a smoke point of approximately 242°C (468°F). Refined olive oil is labeled as "olive oil" or "pure olive oil" — not extra virgin or virgin. It is the primary oil used for deep frying in Mediterranean countries and is also used as a base for blended oils.2
Official Olive Oil Grades
The International Olive Council (IOC) — the international regulatory body for olive oil standards — defines the following olive oil grades:2
Extra Virgin Olive Oil (EVOO)
- Free fatty acid content ≤ 0.8%
- No sensory defects (per IOC-certified taste panel)
- Retains all polyphenols and aromatic compounds
- The only grade with documented health benefits in clinical trials
- Best used: salad dressings, dipping, finishing, low-temperature cooking
Virgin Olive Oil
- Free fatty acid content 0.8–2.0%
- May have minor sensory defects detected by taste panel
- Retains some polyphenols but at lower levels than EVOO
- Acceptable for general cooking use
- Best used: everyday cooking, sautéing
Ordinary Virgin Olive Oil
- Free fatty acid content 2.0–3.3%
- Significant sensory defects
- Rarely found in retail; typically used for refining or industrial purposes
Lampante Virgin Olive Oil
- Not fit for human consumption without refining
- High acidity (>3.3%) and strong sensory defects
- Used only as a raw material for refining into refined olive oil
Refined Olive Oil
- Produced by refining lampante virgin oil using physical and chemical methods
- Free fatty acid content ≤ 0.3%
- No polyphenols, neutral flavor, neutral color
- Smoke point approximately 242°C (468°F)
- Labeled simply as "Olive Oil" or "Refined Olive Oil"
- Best used: high-temperature frying, industrial food production
Olive Pomace Oil
- Extracted from the solid residue (pomace) after mechanical pressing, using solvent extraction
- Refined to remove solvents and impurities
- Not a direct olive product — it's derived from processing waste
- Labeled as "Olive Pomace Oil"
- Best used: industrial frying, not recommended for home use
How Tasting Panels Determine Grade
The IOC requires a trained tasting panel (a group of certified assessors) to evaluate all olive oils for sensory defects. The panel smells and tastes the oil, looking for specific defect descriptors: rancid (the most common), musty, winey, sour, metallic, and others. If any defect is detected at a threshold intensity above zero, the oil cannot be classified as extra virgin.2
How Chemistry Tests Determine Grade
Alongside panel testing, chemical analysis Determines the grade:
Free Fatty Acid (FFA): The percentage of free fatty acids in the oil, indicating the degree of lipolysis (fat breakdown). Lower is better — ≤0.8% for EVOO.
Peroxide Value (PV): The concentration of peroxides (primary oxidation products). Lower is better — EVOO must be ≤ 20 mEq O₂/kg.
K270 Absorbance (UV): A spectrophotometric measurement of oxidation byproducts at 270nm. Elevated K270 indicates secondary oxidation compounds and possible refinement.
Fatty Acid Composition: The percentages of individual fatty acids (oleic, linoleic, palmitic, etc.) — deviations from expected ranges indicate possible adulteration or refinement.
The Polyphenol Difference
The key functional difference between extra virgin and refined olive oil is polyphenol content. Refined olive oil has essentially zero polyphenols — they are destroyed in the refining process. This matters because the health benefits of olive oil (anti-inflammatory, cardiovascular, metabolic) are primarily driven by polyphenols, which exist only in unrefined oils. If you're using olive oil primarily for its health properties, extra virgin is the only appropriate choice.1
References
- [1] European Voice Oil Association — Olive Oil Grades: https://www.evoa.org/grades/
- [2] International Olive Council — Standards: https://www.internationaloliveoil.org/what-we-do/quality/standards/