Olive oil is part of our everyday lives, and yet there are plenty of misconceptions about it. Colour, sediment, the fridge test, the words "cold pressed"… We have checked eight common beliefs against the official texts of the International Olive Council (IOC), EU regulation and scientific research. For each one: the verdict, a sourced explanation and a practical tip.
1. "The greener it is, the better it is"
Verdict: False
In official tastings, the colour is deliberately hidden. The IOC standard for the tasting glass requires a "dark-coloured" glass so that the taster cannot perceive the colour of the oil, eliminating any bias that might distort the assessment (IOC, 2020). Classification as extra virgin depends on the absence of defects and the presence of fruitiness, not on the hue (IOC, 2024). The UC Davis Olive Center points out that colour depends on many factors other than quality: variety, region, climate, fruit ripeness and processing method (UC Davis, 2019).
Tip: judge an oil by its aroma and taste. Our guide to tasting olive oil like a professional explains how.
2. "The fridge test proves an oil is pure"
Verdict: False
The idea: genuine extra virgin olive oil should solidify in the refrigerator. Researchers at the UC Davis Olive Center tested seven samples (good and poor quality extra virgin olive oils, blends with refined oil, refined canola and safflower oils) at 4.7 °C for 180 hours. None solidified completely, the poor quality extra virgin olive oil behaved just like the good one, and a 50% blend also partially solidified. Their conclusion: the fridge test is reliable neither for detecting purity nor for judging quality (UC Davis Olive Center, 2013).
Tip: rely instead on the chemical and sensory analyses published by the producer, and on the harvest date.
3. "Light olive oil contains fewer calories"
Verdict: False
The word "light" refers to the refining of the oil, not its calorie content. The UC Davis Olive Center is clear: all oils provide the same number of calories, namely 9 calories per gram, about 120 per tablespoon (UC Davis, 2019).
Tip: for the same calories, choose an extra virgin olive oil, rich in polyphenols.
4. "Olive oil improves with age, like wine"
Verdict: False
Over time, all olive oils, even the best, eventually turn rancid through oxidation, and their fresh aromas fade (UC Davis, 2019). A study covering 24 months of storage measured a loss of around 30 to 40% of total polyphenols over two years, along with a decline in fruitiness, bitterness and pungency (Ghanbari Shendi et al., OCL, 2020). This is why EU regulation requires the label to state that the oil must be stored away from light and heat (Article 7 of Regulation (EU) 2022/2104).
Tip: look for the harvest year. It is only permitted if 100% of the oil comes from that harvest (Article 11). Our article on reading an olive oil label explains these terms in detail.
5. "Sediment at the bottom of the bottle means the oil has gone off"
Verdict: It depends
An unfiltered oil naturally contains fine particles of fruit and tiny droplets of water that settle. The UC Davis Olive Center explains that some producers filter for clarity and to prevent defects from developing, as this sediment can speed up the development of off-flavours (UC Davis, 2019). The IOC also describes the "fusty/muddy sediment" defect, notably in an oil left in contact with sediment that has fermented without air at the bottom of tanks (IOC, 2024).
The science remains divided. In a two-year study, filtered oil was better protected from hydrolysis and oxidation, but unfiltered oil contained more polyphenols; the authors stress that the literature on the subject is contradictory (Ghanbari Shendi et al., OCL, 2020). A light sediment is therefore not a defect in itself. At Oikos Antalis, our oils are unfiltered: a light sediment is natural.
Tip: store it away from light and heat and avoid pouring out the last of the bottle. If it smells muddy or fermented, that is a defect: see our guide to olive oil defects.
6. "A bitter or peppery oil is defective"
Verdict: False
Quite the opposite. In the official IOC method, fruity, bitter and pungent are classed as "positive attributes". Bitter is defined as the characteristic taste of oil obtained from green olives or olives turning colour, and pungent as a biting tactile sensation typical of oils produced at the start of the season (IOC, 2024). EU regulation even provides intensity terms (intense, medium, light) for these three attributes (Annex II of Regulation (EU) 2022/2104). The real defects listed by the IOC include rancid, fusty/muddy sediment, musty and winey.
Tip: a tingling in the throat after a sip of extra virgin olive oil is nothing to worry about: that is pungency, a sought-after attribute.
7. "Olive oil and extra virgin olive oil are the same thing"
Verdict: False
Regulation (EU) 2022/2104 distinguishes several categories, each with a mandatory description. Extra virgin olive oil is "superior category olive oil obtained directly from olives and solely by mechanical means". Plain "olive oil", on the other hand, is oil "containing exclusively olive oils that have undergone refining and oils obtained directly from olives" (Article 6, Regulation (EU) 2022/2104). In other words, it is a blend of refined oil and virgin oil.
Tip: look for the exact name "extra virgin olive oil" and the description that accompanies it on the back of the bottle.
8. "Cold pressed is always better"
Verdict: It depends
These terms are regulated. "First cold pressing" is reserved for virgin and extra virgin olive oils obtained below 27 °C from a first mechanical pressing in a traditional hydraulic press system. "Cold extraction" is reserved for those obtained below 27 °C by percolation or centrifugation of the olive paste (Article 10 of Regulation (EU) 2022/2104). These terms are therefore real and verifiable, but optional: they say nothing about the condition of the olives, the time before milling or the absence of defects.
At Oikos Antalis, our 100% Koroneiki olives, from four estates in Ilia (Peloponnese), are hand-picked and cold extracted the same day. Our laboratory analyses are published.
Tip: combine the temperature claim with other evidence: harvest year, analyses, sensory profile. Discover our olive oil bottles.
Sources
- Sensory Analysis of Olive Oil: Standard, Glass for Oil Tasting (COI/T.20/Doc. No 5/Rev. 2), International Olive Council, 2020
- Sensory Analysis of Olive Oil: Method for the Organoleptic Assessment of Virgin Olive Oil (COI/T.20/Doc. No 15/Rev. 11), International Olive Council, 2024
- Commission Delegated Regulation (EU) 2022/2104 on marketing standards for olive oil, European Commission, EUR-Lex, 2022
- Refrigeration Is Not a Reliable Method for Assessing Olive Oil Quality and Purity, X. Li, S. C. Wang, D. Flynn, UC Davis Olive Center, 2013
- Ten Myths and Facts About Olive Oil, S. C. Wang, J. D. Flynn, UC Davis Olive Center, 2019
- Effects of filtration process on the minor constituents and oxidative stability of virgin olive oil during 24 months storage time, E. Ghanbari Shendi, D. Sivri Ozay, M. T. Ozkaya, OCL, 2020
And at Oikos Antalis?
- Bitterness and pungency: the signature of our polyphenols, 424 and 359 mg/kg in the 2026 harvest, against an EU threshold of 250 mg/kg.
- A light deposit: our oils are unfiltered, so it is natural.
- Extraction: cold, on the day of harvest, after 25 minutes of malaxation.
- Verified extra virgin: acidity of 0.33% and 0.42% against a limit of 0.8%, zero defects at the 2026 panel for Skourochori, no pesticide residue detected.
The reports are on our Analyses page.