Virgin, crude, raw, natural, extra virgin, first cold pressed. On a shelf of oils, these terms all look alike. Yet, they do not mean the same thing at all.
Here's what each one actually means, and how to read an oil bottle without being swayed by marketing.
What's at stake in an oil
A vegetable oil is not just a fat. It's a concentrate of fragile compounds: essential fatty acids, vitamin E, polyphenols, phytosterols, carotenoids. These molecules have a documented role in skin barrier function, inflammation, hormonal balance, and cell protection.
The problem is that these compounds are precisely those that industrial processes destroy first. An oil can therefore be perfectly edible, perfectly stable, and yet have no nutritional value whatsoever.
The difference between the two is not visible. It is read on the label, provided you know what to look for.
The industrial process: hot pressing and refining
For efficiency, oilseeds and fruits can be pressed at high temperatures. Heat thins the oil and increases the extraction rate. More oil, less raw material, better yield.
The crude oil obtained then undergoes a series of operations: degumming, neutralization, decolorization, deodorization. Each removes something. Phospholipids, pigments, volatile compounds, some tocopherols, and natural antioxidants.
The result is an oil with a neutral taste, clear, long-lasting, very stable for cooking. But stripped of most of what made it worth consuming.
These oils represent the vast majority of what is sold in supermarkets.
Decoding the mentions
"Virgin oil from…"
This is the most protective mention, and the only one that is clearly legally binding.
Decree n° 2008-184 of February 26, 2008 reserves the designation "Virgin oil from…" for oils obtained by mechanical processes, clarified exclusively by physical means, having undergone neither chemical treatment nor any refining operation.
Three concrete guarantees: no solvent extraction, no refining, no additives.
But a crucial, often ignored nuance: "virgin" does not prohibit heat. The Codex Alimentarius defines virgin oils as obtained by mechanical processes and application of heat, while cold-pressed oils are obtained without any application of heat.
A virgin oil may therefore have been heated. This is why the second mention matters.
"First cold pressed"
This mention is reserved for oils that have undergone no thermal process. Any temperature increase can only be linked to the pressing and mechanical extrusion process of the seed or fruit itself.
In other words: preheating the seeds is forbidden. The only heat tolerated is that generated by the friction of the press itself.
This is a real constraint. But it has a limit that needs to be known: it defines a process, not a temperature. A fast press at high flow can raise the oil to 60 or 70 °C by simple friction, without any external heat having been applied.
Only one exception in all regulations: extra virgin olive oil, whose extraction temperature is capped at 27 °C. For seed oils, no specific numerical threshold exists.
Practical consequence: "virgin" and "cold pressed" are cumulative mentions, not synonyms. A quality oil must bear both. And to go further, the only truly discriminating information is the press outlet temperature, which only a transparent producer will disclose.
"Extra virgin"
This designation applies only to olive oil. It does not legally exist for any other vegetable oil.
It requires exclusively mechanical extraction, no chemical treatment, free acidity lower than 0.8 g per 100 g, and the absence of any sensory defect during tasting.
The two degradations not to be confused
Two parameters measure the quality of an oil. They are often confused, yet they describe different phenomena.
Free acidity
In an intact oil, fatty acids are bound to a glycerol molecule, in groups of three. This is the stable form of lipids: the triglyceride.
Free acidity measures the proportion of fatty acids that have detached from this skeleton. This detachment, called hydrolysis, is caused by damaged or fallen fruits, too long a delay between harvesting and crushing, and the presence of water and heat.
Free acidity is therefore an indicator of the quality of the raw material and the speed of the process. An olive oil at 0.2% indicates healthy fruits crushed within hours of harvest.
It is expressed as a percentage for olive oil, and as an acid value for other vegetable oils. The Codex sets a maximum of 4.0 mg KOH/g for virgin and cold-pressed oils, compared to 0.6 mg KOH/g for refined oils.
Oxidation
Oxidation is a distinct phenomenon. Oxygen attacks the double bonds of unsaturated fatty acids and produces degradation compounds. It causes rancidity, unpleasant odors, and tastes.
It is measured by the peroxide value, the anisidine value, and their combination, the TOTOX. The Codex caps the peroxide value at 15 milliequivalents of active oxygen per kilogram for virgin and cold-pressed oils.
Key point: an oil can have impeccable acidity and already be oxidized. For oils rich in polyunsaturated fatty acids, oxidation is by far the most critical parameter. Acidity alone says nothing about their freshness.
The container: an underestimated criterion
It is probably the most visible quality signal, and the most often ignored.
Light is one of the main factors of oil degradation. Ultraviolet radiation triggers photo-oxidation, which attacks unsaturated fatty acids and degrades polyphenols and tocopherols. An oil exposed to light loses some of its active compounds well before its expiration date.
Transparent glass offers no protection. Tinted glass filters some of the radiation; dark and opaque glass filters even more.
A brand that invests in a protective container signals two things. First, that it has formulated an oil containing compounds worth protecting. Second, that it accepts an additional cost that only serves to preserve product quality, without immediate marketing benefit.
Conversely, an oil rich in polyunsaturated fats sold in translucent plastic or clear glass raises a simple question: why protect something claimed to be valuable with the cheapest container on the market?
The format also matters. An oil rich in omega-3 oxidizes as soon as it is opened. A small volume, consumed quickly, preserves better than a large container started months ago.
What to check, in summary
On the label
- The mention "virgin", followed by the name of the seed or fruit
- The mention "first cold pressed", as a complement and not a replacement
- An organic certification issued by an approved control body
- A precise geographical origin
On the container
- Dark, tinted, or opaque glass
- Format suitable for rapid consumption
- Hermetic seal
By taste
- A distinct color, never translucent
- A pronounced taste, true to its origin
- For olive oil, a pronounced bitterness and pungency
From the producer, if the information is accessible
- The harvest date
- The press outlet temperature
- Oxidation indices: peroxide, anisidine, TOTOX
- Free acidity
- For olive oil, the polyphenol content and the analysis method used
Quality oil costs more. Not due to positioning, but because the yield of cold extraction is lower, the raw material must be impeccable, and traceability and analysis have a real cost.
This cost is what separates a living oil from an empty oil.