Cold Pressed Olive Oil: A Legal Term Most Labels Misuse

Cold pressed olive oil is oil taken from olives whose crushed paste was never allowed above 27°C — and, unusually for a phrase on a food label, that number is law. The labelling regulation in force in Great Britain defines two versions of the claim exactly: “first cold pressing”, reserved for oils from traditional hydraulic presses, and “cold extraction”, the wording for the centrifugal method that makes almost every modern bottle. The catch is that the phrase people search for sits between the two: most oils sold as “cold pressed” were never pressed at all. This guide covers where cold pressing comes from, what the regulation reserves, why 27°C is the number the law chose, and what a buyer should read on the label instead of the phrase.

Cold pressed olive oil, as buyers use the words, means oil separated from olive paste kept below 27°C. The law splits that idea by machine: “first cold pressing” for hydraulic press systems, “cold extraction” for centrifugation or percolation.

Plate I · IllustrationRecord

Where does “cold pressing” come from?

From millennia of actual presses. Until living memory every olive mill worked the same way: olives crushed to a paste — under stone wheels, for most of that history — the paste spread onto woven fibre discs, the discs stacked into a column, and the column squeezed, first by lever and screw, later by hydraulic ram. Oil and fruit water ran off together and were left to part by settling.

Both halves of the phrase once carried information. First pressing: the opening squeeze, on fresh paste, gave the finest oil. The spent cake still held oil, so it was broken up, doused with hot water and pressed again — a second pressing, hotter, harsher and noticeably worse, sold cheaper or sent for refining. Cold: whether the mill had used heat — warm water, warmed paste — to lift its yield on the first squeeze. “First cold pressing” was the shortest honest answer to both questions: the first squeeze, unheated. The phrase earned its premium when there was a press to be first on and a temptation to run it warm.

How is olive oil made now — does anyone still press it?

At the quality end of the market, almost nobody. Milling technology settled into three families — pressure, percolation and centrifugation, the classification used in Di Giovacchino’s standard review of processing — and since the 1970s the continuous centrifugal decanter has displaced the press almost completely. A modern line runs without pause: leaves blown off and fruit washed, a steel crusher, a slow-stirred malaxer, then a horizontal decanter centrifuge that spins the paste and draws off oil, water and solids in one motion, with a vertical centrifuge to polish the oil after it. Percolation — steel blades dipped into the paste so that oil clings to the metal and drips free — survives in a handful of mills. None of this troubles the definitions: the international trade standard defines virgin olive oil as oil obtained “solely by mechanical or other physical means” under conditions — thermal conditions above all — that do not alter it, and a decanter qualifies as fully as a ram.

The press lost for good reasons. It was slow and batch-bound where the decanter is continuous. Worse, the fibre mats held moist paste residue between pressings, where it fermented — pressed oils picked up exactly the musty, fusty defects the extra virgin panel test exists to catch. Stainless steel, washed daily, removed that risk, and Di Giovacchino’s review adds the modern refinement: decanters run with little or no added process water leave more of the fruit’s phenolics in the oil.

Two consequences follow for the label. There is no second pressing left to be first of — a decanter takes the oil once, and what remains goes to the pomace refiners, not back under a ram. And a mill that owns no press cannot meaningfully claim pressing at any temperature. Modern premium oil is not cold pressed. Correctly labelled, it is something else.

Fig. I · Where the words attachedDiagram

One phrase, two machines. The press line is where “first” and “cold” earned their meaning; the continuous line that replaced it gives the words nowhere to land.

The press lineUntil living memory, every mill — batch by batch

1. Olives crushed to a pasteUnder stone wheels, for most of that history
2. Paste spread onto woven fibre discsThe discs stacked into a column
3. The column squeezedFirst by lever and screw, later by hydraulic ram“first”The opening squeeze, on fresh paste — the finest oil“cold”Run unheated — no warm water or warmed paste to lift the yield
4. Oil and fruit water run off togetherLeft to part by settling
5. The spent cake pressed againBroken up, doused with hot water — a second pressing, hotter, harsher and noticeably worse, sold cheaper or sent for refining

Where the words attach

“First cold pressing” was the shortest honest answer to both questions: the first squeeze, unheated.

The continuous lineSince the 1970s — runs without pause

1. Leaves blown off, fruit washed
2. Steel crusher
3. Slow-stirred malaxer
4. Horizontal decanter centrifugeSpins the paste and draws off oil, water and solids in one motion
5. Vertical centrifugePolishes the oil after it

Where the words attach

Nowhere. Centrifugation is not pressing, and nothing in a continuous process is first — a decanter takes the oil once, and what remains goes to the pomace refiners, not back under a ram.

Modern premium oil is not cold pressed. Made cool, a decanter oil may say “cold extraction” — and may not say “first cold pressing”.

What does the law actually reserve?

In Great Britain, olive oil labelling is governed by assimilated Regulation 29/2012, enforced through The Olive Oil (Marketing Standards) Regulations 2014, with APHA inspecting labels against it. Article 5 lists the optional quality indications a label may carry, and two entries are the whole story here:

• “First cold pressing” may appear only on extra virgin or virgin olive oil “obtained at a temperature below 27°C from a first mechanical pressing of the olive paste by a traditional extraction system using hydraulic presses”.
• “Cold extraction” may appear only on extra virgin or virgin olive oil “obtained at a temperature below 27°C by percolation or centrifugation of the olive paste”.

Read together: the same temperature line, different machinery, no overlap. A hydraulic-press oil made cool may say “first cold pressing”. A decanter oil made cool may say “cold extraction” — and may not say “first cold pressing”, because centrifugation is not pressing and nothing in a continuous process is first.

So the phrase this page is named for is the odd one out. A bottle that says “cold extraction” was labelled by someone who has read the regulation; a centrifuged oil that says “first cold pressed” was labelled by someone reaching for romance. Between them sits “cold pressed”, which at best means “cold extraction” said imprecisely, and at worst means nothing that was ever measured.

One honesty note: Article 5 requires no certificate. The temperature claim stands on the mill’s process records — like every quality word on a label, it is as good as the documentation behind it.

Why does the 27°C line matter?

Because it regulates the step between crushing and separation: malaxation. Crushing bursts the fruit’s cells, but the oil sits in the paste as microscopic droplets, so the paste is stirred slowly — typically twenty to forty-five minutes — while droplets meet and coalesce into oil the decanter can take. Malaxation is where a mill earns its yield, and temperature is its biggest lever: warm the paste and the oil thins, coalescence quickens, and more oil comes out of the same fruit. Heat, for a mill, is nearly free money.

What it costs is composition. Clodoveo’s overview of the malaxation literature puts temperature, time and oxygen exposure as the three variables that decide what ends up in the bottle. Cooler, shorter malaxation preserves the two families of compounds that make a fresh oil worth more: the phenolics — the bitter, peppery secoiridoids, oleocanthal’s throat-catch among them — which degrade and wash out as the paste runs warmer, and the volatiles, the cut-grass and green-leaf aromas made by the fruit’s own enzymes as the paste stands, whose production falls away as temperature climbs. The two dials are not equal: in the trial that varied both across a wide range, (E)-2-hexenal — the grassiest of those volatiles — changed with malaxation temperature and not with time, and the oils made at the temperature extremes were the most sharply different of all (Kalua and colleagues, 2006). Servili and colleagues, optimising those same variables cultivar by cultivar, landed at 22–26°C — under the legal line, not at it. Warmth favours what nobody wants: faster oxidation, and a flatter, older-tasting oil.

Fig. II · The 27°C lineDiagram

Both reserved wordings share the same threshold: the olive paste must stay below 27°C, above all during malaxation — the slow stir, typically twenty to forty-five minutes, where droplets coalesce and a mill earns its yield.

Olive-paste temperatureDrawn from 22°C to the legal line

22°C27°C

22–26°COptimisation trials

below 27°CThe legal line

Servili’s optimum — 22–26°C

Optimising temperature and time cultivar by cultivar, Servili and colleagues landed at 22–26°C — under the legal line, not at it.

The legal line — below 27°C

The regulation’s phrase is “obtained at a temperature below 27°C”, the same threshold for both reserved wordings, and it refers to the olive paste. An oil malaxed warmer can lawfully be extra virgin — it just may not print the cold wordings.

What warming the paste moves

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Oil yield — rises as the paste warmsThe oil thins, coalescence quickens, and more oil comes out of the same fruit. Heat, for a mill, is nearly free money.

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Phenolics — degrade and wash out as the paste runs warmerThe bitter, peppery secoiridoids, oleocanthal’s throat-catch among them.

▼

Aroma volatiles — production falls away as temperature climbsThe cut-grass and green-leaf aromas made by the fruit’s own enzymes. In the trial that varied both dials, (E)-2-hexenal — the grassiest — changed with malaxation temperature and not with time (Kalua and colleagues, 2006).

The line caps that trade. A true cold claim, on either wording, is a promise that the mill ran the paste cool and left oil in the pomace on purpose.

That is the point of the rule. The 27°C line is not press nostalgia; it caps the yield-against-quality trade at the point where chasing litres starts to strip character out of them. A true cold claim, on either wording, is a promise that the mill left oil in the pomace on purpose — which is also the honest reason such oils cost more. The compounds the rule protects are measurable per batch: what a high phenolic content means on a shelf is at high-polyphenol olive oil, and what the research literature makes of the compounds themselves is read at olive oil polyphenols.

Is cold pressed olive oil better?

Cooler extraction is one real quality lever, not a verdict. Other levers move an oil at least as much: the condition of the fruit at the crusher, the hours between tree and mill, and the tank and bottle conditions afterwards. The strongest compositional lever of all is how early the fruit was picked — in the largest survey of Greek oils, 5,764 samples measured by NMR, phenolic content fell steadily from the September pickings to the midwinter ones — and it comes at a steeper cost in yield, the honest economics behind early harvest olive oil. A cold-extracted oil milled from overripe or bruised fruit is a cool, faithful record of dull fruit.

The grade also does more work than the phrase. Extra virgin is defined in assimilated Regulation 2568/91: mechanical extraction, free acidity of no more than 0.8%, and a taste panel finding a median of defects of zero and some fruitiness — a sensory examination no cold wording substitutes for. Note the independence in both directions: an oil malaxed above 27°C can lawfully be extra virgin (it just may not print the cold wordings), and a below-27°C oil from fermented fruit will fail the panel however cold it ran. The grade is the floor; the cold wording is one detail above it.

What should you look for instead of the phrase?

• The grade, stated properly. In Great Britain extra virgin must carry the fixed category sentence “superior category olive oil obtained directly from olives and solely by mechanical means”. That sentence, plus the panel test behind the grade, does most of what buyers hope “cold pressed” does.
• A harvest date. Permitted only where all of the bottle’s contents come from a single harvest year, given as the marketing year or as the month and year of extraction. Freshness moves an oil more than press vocabulary, and a bottle willing to date itself is making a checkable statement.
• “Cold extraction”, spelled correctly. A small but real signal that the label was written from the regulation rather than the thesaurus.
• The acidity rule. A label may state acidity only if the peroxide value, wax content and UV absorbency appear in the same field of vision in the same size — the analytics travel as a set of four or not at all. A lone acidity boast is off-spec; the full set is a mill showing its laboratory work.
• Origin, exactly. A designation of origin is mandatory on extra virgin and virgin oil, and a protected name carries a certification scheme behind it rather than a mood.

The line-by-line walkthrough of a compliant label is at how to read an olive oil label, and how to weigh all of this on a UK shelf is at best olive oil UK.

Readers who came here from the honey side of this site will recognise the shape of the problem, inverted. On the honey shelf, “raw” is a word no UK law defines, worth exactly what per-batch evidence makes it — the case set out in what is raw honey. The olive oil shelf fails the other way round: its cold words are defined down to the degree and the machine, and the shelf borrows them loosely anyway. Undefined words drift; defined ones get taken. The discipline that answers both is the same — records against the batch.

Where THYMELIA stands

THYMELIA is a UK house for single-origin Greek foods: raw Cretan thyme honey from Chania first, and now the groundwork for a second line — Greek extra virgin olive oil from the olive country around Kalamata, mapped from the top at olive oil and, for the region, at Kalamata olive oil. There is no shop and no stock, and we are not naming a date for any of it. What we can state now is the standard we intend to be held to: an oil of ours will be a centrifuged oil, extracted below 27°C and labelled “cold extraction” — the wording that will be true — with the mill’s temperature records held per batch, the same per-batch discipline the honey side sets out at testing, and the same care about whom we buy from set out at sourcing. The words “first cold pressing” will not appear on our label, because we will not own a press.