A label says "extra virgin". A laboratory analysis proves it. At Oikos Antalis, we publish the reports for every cuvée, harvest after harvest, but a laboratory report is not always easy to read. Here, line by line, is what an olive oil analysis measures and which figures to look at.
1. Acidity: the first criterion for extra virgin olive oil
Free acidity, expressed as a percentage of oleic acid, measures how much the fruit has degraded before pressing. The healthier the olives and the faster they are pressed, the lower it is.
- Regulatory limit for extra virgin olive oil: 0.8% maximum.
- A great oil is often below 0.3%.
- Our cuvées: 0.33% for Skourochori and 0.42% for Agios Ilias (2026 harvest), 0.19% for Paliovarvassena (2025 harvest).
2. Peroxide value: oxidation
It measures the oil's oxidation, linked to air, light and time. The limit for extra virgin olive oil is 20 meq O2/kg maximum. A low figure indicates a fresh, well-protected oil.
3. K232, K270 and ΔK: ultraviolet absorbance
These three values, measured by spectrophotometry, detect more advanced oxidation or possible refining. The limits for extra virgin olive oil are 2.50 for K232, 0.22 for K270 and 0.01 for ΔK. An oil above these limits cannot be sold as extra virgin.
4. Polyphenols: the real measure of quality
Polyphenols are not among the mandatory criteria, and yet they are the most telling figure. They are expressed in mg/kg.
- Above 250 mg/kg, the oil may carry the European health claim on polyphenols (EU Regulation 432/2012).
- Above 400 mg/kg, the content is considered very high.
- Our cuvées, 2026 harvest: 424 mg/kg for Skourochori, 359 mg/kg for Agios Ilias.
5. Oleocanthal: the freshness marker
This is the polyphenol that catches the throat. It is abundant in early-harvest oils and declines over time. Laboratories often use a reference of 135 mg/kg. For the 2026 harvest, our cuvées show 176 mg/kg for Skourochori and 152 mg/kg for Agios Ilias.
6. Pesticide residues
A multi-residue screening looks for several hundred molecules. The expected result is simple: "not detected" or below the limit of quantification. Our 2026 screening found zero pesticide residues.
Three habits before you buy
- Ask for the analysis. A serious producer can provide it for each harvest.
- Check the year. An analysis applies to one specific harvest, not to all of them.
- Be wary of figures that never change. An oil from a single terroir varies from one year to the next; that is normal.
All our full reports can be downloaded, cuvée by cuvée, from our Analyses page. To go further, read our article on polyphenols.