Frequently Asked Questions
What is refined olive oil?
Refined olive oil (also called "pure olive oil," "light olive oil," or "olive oil — refined") is olive oil that has been processed to remove defects, neutralize flavor, and raise the smoke point. For a complete overview, see our Extra Virgin Olive Oil guide.The refining process uses physical and chemical methods — including neutralization with alkaline substances, bleaching with activated earth, and deodorization at high temperature — to produce an oil that is technically olive oil but lacks the distinctive flavor, aroma, and most of the beneficial compounds of extra virgin olive oil. Refined olive oil must meet the same basic fatty acid composition standards as EVOO but fails the sensory evaluation and has negligible polyphenol content. It is not a low-Quality version of EVOO — it is a different product category with different characteristics and uses.1
Should I use refined or extra virgin olive oil?
Use extra virgin olive oil for: any application where the oil will be tasted — salad dressings, bread dips, finishing dishes, drizzling over food after cooking. The flavor and health benefits of EVOO are irreplaceable in these applications.
Use refined olive oil for: high-heat cooking (deep frying above 375°F) where you want a neutral-flavored cooking fat with a high smoke point and the practical advantages of olive oil's fatty acid profile over seed oils. Refined olive oil has a smoke point approximately 465°F (240°C) vs. EVOO's 375–410°F, making it more suitable for sustained high-heat cooking. However, for sautéing, roasting, and general cooking, EVOO is still a better choice than refined — the monounsaturated fatty acid profile makes it more oxidation-resistant than polyunsaturated seed oils even at moderate cooking temperatures.1
The Refining Process: What Gets Removed
The refining of olive oil (called "rugginazione" in Italian) is designed to convert lampante oil — the low-quality oil from the first physical pressing that fails EVOO standards — into a product that is technically edible and neutral in flavor. The process involves three main stages:
Neutralization: The free fatty acids in lampante oil (which give it its acidic, sometimes rancid taste) are removed using an alkaline solution (sodium hydroxide). This produces an oil with free fatty acidity close to zero — the legal minimum for all olive oil grades.
Bleaching: The bleached oil is then treated with activated earth (fuller's earth or activated charcoal) at 80–100°C to remove pigment compounds (chlorophyll, pheophytin) and any remaining oxidation products. This gives refined olive oil its characteristic pale, golden-yellow color — removed of the deep green of fresh EVOO.
Deodorization: The bleached oil is steam-distilled at high temperature (200–230°C) under vacuum to remove volatile flavor compounds — the fruity, grassy, peppery aromatics that characterize EVOO. This produces an essentially flavorless and odorless oil.
The result: an oil that is chemically olive oil (same fatty acid profile as the source olives) but stripped of its polyphenol fraction, its aromatic complexity, and its characteristic flavor. The reason to produce this oil is entirely commercial — it provides a neutral, high-heat cooking medium derived from olives at a lower price point than EVOO.1
What's Lost: The Polyphenol Factor
The refining process removes virtually all of the approximately 30+ phenolic compounds present in fresh EVOO. This is not a minor nutritional difference — it represents the elimination of the primary mechanism by which olive oil benefits health. Without polyphenols, refined olive oil is essentially a monounsaturated fat with a favorable fatty acid profile but none of the anti-inflammatory, antioxidant, or cardioprotective effects documented for EVOO.
To illustrate the magnitude: a typical high-phenolic EVOO might contain 500 mg/kg of total polyphenols. Refined olive oil typically contains less than 5 mg/kg — a 100× difference. The EFSA health claim for olive oil polyphenols (protection of blood lipids from oxidative stress) only applies to olive oils with polyphenol content above 5 mg/kg and consumed at a minimum daily dose — which effectively means the claim applies to EVOO, not refined olive oil.^12
Fatty Acid Profile: What Remains
The fatty acid composition of refined olive oil is essentially identical to the source oil — the refining process does not alter the triglyceride structure or the oleic acid content. Both EVOO and refined olive oil from the same olives will have approximately 70–80% oleic acid (monounsaturated), 8–15% linoleic acid (polyunsaturated), and minor amounts of other fatty acids. This is why refined olive oil retains the practical cooking advantages of olive oil — it is still more oxidation-resistant at high temperatures than polyunsaturated seed oils, simply because it retains its high monounsaturated content.
The practical implication: if you are deep frying at temperatures above 375°F for extended periods, refined olive oil is technically superior to EVOO (higher smoke point) and superior to most seed oils (better fatty acid stability). However, for virtually all home cooking — sautéing at 350°F, roasting at 400°F, baking — EVOO is adequate and provides the added benefit of its polyphenol content.^13
Price and Quality Comparison
Refined olive oil typically costs 30–50% less than EVOO from the same producer — the refining process allows producers to use lower-quality olives (or olives that have degraded during storage) and still produce a viable cooking oil. This makes refined olive oil the dominant sales volume product in many markets, particularly in the United States, where most "olive oil" sold in supermarkets is a blend of refined and cold-pressed oils (marketed as "olive oil" rather than "extra virgin").
For cooking-heavy households (who go through 2+ liters per month on high-heat applications), refined olive oil is a legitimate cost-saving choice — but the saving comes at the cost of all the flavor and most of the health benefits. A better strategy: buy a quality EVOO for raw use and finishing, and use refined olive oil only for the specific high-heat applications (deep frying) where its smoke point advantage is meaningful.1
References
- [1] Olive Oil Source — Olive Oil Classification: https://www.oliveoilsource.com/info/olive-classification
- [2] PMCID PMC6770583 — Olive Oil Phenolic Compounds: https://pmc.ncbi.nlm.nih.gov/articles/PMC6770583/
- [3] International Olive Council — Culinary Cultures: https://www.internationaloliveoil.org/our-products/culinary-cultures/