What Does 'Cold Pressed' Really Mean?

The terms ​“cold pressed,” ​“first pressed” and ​“first cold pressed” fre­quently appear on the vir­gin and extra vir­gin olive oil bot­tles that line super­mar­ket shelves and the stands of farmer’s mar­kets.

These out­dated pro­duc­tion terms are meant to con­note that the oil is of supe­rior qual­ity, obtained from the first press­ing in a tra­di­tional mill with­out exces­sive heat that would dimin­ish its fra­grant aro­mas and fla­vors as well as many of its health­ful qual­i­ties.

However, the vast major­ity of extra vir­gin olive oil is now made using a cen­trifuge and not a press, mak­ing these terms more of a mar­ket­ing ploy than an actual pro­duc­tion descrip­tion.

These days, vir­gin and extra vir­gin olive oils are gen­er­ally extracted at tem­per­a­tures lower than 27 °C (80.6 °F).

Olive oil extracted at higher tem­per­a­tures will fail to have the nec­es­sary organolep­tic and chem­i­cal com­po­si­tions of vir­gin and extra vir­gin olive oils, mak­ing the ter­mi­nol­ogy ​“cold-pressed extra vir­gin” redun­dant.

Where did these terms come from?

Until the mid-twen­ti­eth cen­tury, olive oil was made almost exclu­sively using a tra­di­tional or hydraulic press and the term ​“first pressed” described the vir­gin and extra vir­gin olive oil pro­duced from freshly har­vested olives.

Since olives are har­vested at the end of autumn and the begin­ning of win­ter, the fruit was cool when it arrived at the mill to be processed. What seeped out from the press and trick­led down into con­tain­ers below was vir­gin or extra vir­gin olive oil, if it met the qual­ity char­ac­ter­is­tics of the grades.

After this first press removed the best oil from the olives, many pro­duc­ers would add hot water to the left­over pits and pulp of the fruit and press it all again.

The heat of the water removed the aro­mas of the oil, depleted its polyphe­nols and degraded the fla­vor. As a result, the sec­ond press was of far infe­rior qual­ity and was used as fuel for lamps — hence the term lam­pante.

If olive oil isn’t pressed, how is it made?

These days, olive oils that qual­ify as vir­gin or extra vir­gin are extracted with­out exces­sive heat, reflect­ing how olive mills have been updated over the past sev­eral decades.

Olives are har­vested in the autumn and win­ter – increas­ingly at night — and milled quickly to avoid the degra­da­tion that heat can cause.

Instead of being pressed, the fruits are poured into metal crush­ers. Once the olives have been crushed into a paste and malaxed – slowly churned or mixed to allow smaller droplets of oil to aglom­er­ate into larger ones – the result­ing paste is trans­ferred to a cen­trifuge where the oil is sep­a­rated from every­thing else.

The mod­ern milling process keeps the tem­per­a­ture of the olive paste below 27 °C to pre­serve the aro­mas, fla­vors and ben­e­fi­cial com­pounds of the oil.

In fact, any oil that is not care­fully extracted with­out exces­sive heat will not qual­ify as vir­gin or extra vir­gin when sub­mit­ted to a tast­ing panel or chem­i­cal analy­sis, which makes ​“cold-pressed” or ​“cold extracted” extra vir­gin olive oil a redun­dant term.

The E.U. gives ​‘first cold pressed’ a new mean­ing

While ​“first cold pressed” and ​“cold extracted” are largely mean­ing­less attri­bu­tions put on extra vir­gin olive oil labels, the European Union has set out to change this.

The 27-mem­ber trad­ing bloc has set legal def­i­n­i­tions of the two terms in order to set tra­di­tion­ally-pro­duced olive oils apart from mod­ern com­peti­tors.

“The indi­ca­tion ​‘first cold press­ing’ may appear only for extra vir­gin or vir­gin olive oils obtained at a tem­per­a­ture below 27 °C from a first mechan­i­cal press­ing of the olive paste by a tra­di­tional extrac­tion sys­tem using hydraulic presses,” the European Union wrote in its mar­ket­ing stan­dards leg­is­la­tion for olive oil.

“The indi­ca­tion ​‘cold extrac­tion’ may appear only for extra vir­gin or vir­gin olive oils obtained at a tem­per­a­ture below 27 °C by per­co­la­tion or cen­trifu­ga­tion of the olive paste.”

Finding real extra vir­gin olive oil

“Cold pressed,” ​“first pressed” and ​“first cold pressed” are all used to con­vince con­sumers that the olive oil they are pur­chas­ing is high qual­ity.

Outside of the European Union, there are few to no rules or reg­u­la­tions on how these terms can be used, so they can be applied to any type of olive oil.

The terms that really mat­ter are ​“vir­gin” and ​“extra vir­gin” which means an olive oil meets the inter­na­tion­ally-rec­og­nized qual­ity stan­dard for the grade.

The Official Guide to the World’s Best Olive Oils con­tains expert reviews and detailed infor­ma­tion for more than five hun­dred high-qual­ity extra vir­gin olive oils from dozens of coun­tries.

• Phys.org
• European Union