How to spot fake or low-grade olive oil

How common is fake or mislabelled olive oil?

The European Commission's food alert report says olive oil “is reputed as one of the foods most vulnerable to fraud in Europe”. In 2024, EU countries exchanged 130 notifications on olive oil through the EU's food alert network; 15% were confirmed as cross-border fraud. The problems reported include oil sold as a higher grade than it is, false labelling, and dilution with cheaper oils. ²

EU countries also run conformity checks on olive oil on the market. In 2024, 17.8% of 4,154 label checks and 31.3% of 3,083 category checks found a non-conformity. These checks target risky products on purpose, so the Commission warns that the figures do not show the share of bad oil on the market as a whole. ¹

Not every failure is fraud. The Commission notes that olive oil degrades with heat, light and time, so a genuine extra virgin oil kept badly can drop below its grade before it is sold. ¹

What are the good signs and the warning signs?

What should you check on the label?

• Category name. Only “extra virgin olive oil” is the top grade. A bottle labelled just “olive oil” is a blend of refined and virgin oils, and olive pomace oil may not be called olive oil at all. ³ See olive oil grades explained.
• Origin. The IOC standard requires the country of origin on the label. In the EU, extra virgin and virgin olive oils must state their origin. ^3,4
• Dates. The IOC standard requires a “best before end” date by month and year. ³ In the EU, a harvest year may only be shown if 100% of the oil comes from that harvest. ⁴ The UC Davis Olive Center advises choosing oil within 15 months of its harvest date, not its best-before date. ⁶
• Producer and lot. The label must name the manufacturer, packer or seller, and each container must carry a lot code. ³
• Acidity claims. In the EU, a maximum acidity may only appear on the label together with the peroxide value, wax content and UV absorbance, in the same size and field of view. ⁴
• “First cold pressing” or “cold extraction”. In the EU these terms are reserved for extra virgin and virgin oils obtained below 27 °C. ⁴

Does the bottle or tin matter?

Yes. The International Olive Council names light as the main threat to olive oil quality and heat as the second. It recommends keeping oil in a dark place, or covering a clear bottle, and storing it between 13 and 25 °C. ⁵

Once opened, air speeds up oxidation, so the IOC suggests containers you'll finish in 1 to 3 months, and using an opened bottle within that time. It advises against iron containers. ⁵ For storage at home, see the FAQ.

Does the fridge test work?

No. The idea is that real extra virgin olive oil solidifies in the fridge. In 2013 the UC Davis Olive Center kept seven oils, from high-quality extra virgin to refined canola, at 4.7 °C. Nothing changed after 60 hours. After 5 days, the three samples with at least 50% virgin olive oil showed some congealing at the bottom, but none fully solidified. ⁶

Its conclusion: the fridge test is unreliable for judging whether an oil is made from olives, and it says nothing about quality. How much an oil clouds in the cold depends on its waxes and fatty acids, which vary from oil to oil. ⁶

Can color or price tell you anything?

Color can't. Official tasting panels use dark-colored glasses precisely so that tasters can't see the oil's color and be biased by it. ⁷ So a deeper green is not, by itself, a sign of a better oil.

Price can't prove quality either. It tells you what the seller asks, not what a lab or panel found. A very low price for an oil sold as extra virgin is a reason to look harder at the label, not proof of fraud.

What does a real test involve?

Confirming a grade takes two things. First, a laboratory measures chemical limits such as free acidity, peroxide value, UV absorbance and fatty acid ethyl esters, plus purity tests that can point to blending with lower-grade or other vegetable oils. ^1,3 Second, a panel of 8 to 12 selected and trained tasters scores code-numbered samples from standard dark glasses. For extra virgin, the median score for defects must be zero and the median for fruitiness above zero. ^3,7,8

You can't run those tests at home. You can, though, learn to recognise the most common defects: fusty (fermented olives), musty, winey-vinegary and rancid. ⁸ Our tasting guide shows you how.

How can you check Leptis Magna?

Leptis Magna is a Libyan extra virgin olive oil, early harvest and cold pressed within hours of picking, with free acidity of 0.4% or less. Apply the same checks to it: read the label, then taste it next to another oil.