Travel Guide
How olive oil is made
Extra virgin olive oil is, at heart, the simplest food imaginable: fresh olive juice. No chemistry, no heat, no refining — just fruit, crushed and separated, within hours of the harvest. That simplicity is exactly why quality depends on getting every step right. Here is how great oil is made, and what the words on the label really mean.
Everything begins in the grove, usually between October and December. The single biggest decision is when to pick. Harvest early, while the olives are still green or just turning, and you get less oil per fruit but far more flavour, aroma and polyphenols — greener, more intense, more peppery, longer-lasting oil. Harvest late, when the fruit is fully ripe and black, and you get more oil, but milder, sweeter and less stable. The finest oils are almost always early-harvest.
Just as important is speed. Once picked, olives begin to ferment and degrade, so the best producers mill the same day. Olives left to pile up develop the classic "fusty" defect (atrojado, from the heap or troje).
At the mill (almazara), the olives are washed and then crushed — traditionally between great stone wheels, today usually by stainless-steel hammer mills — into a paste, stones and all. The paste is then slowly stirred in a process called malaxation, which lets the tiny oil droplets join into larger ones so they can be separated. This is done at low temperature — below 27 °C — to protect the delicate aromas and antioxidants.
The oil is then separated from the water and solids. Traditional mills spread the paste on mats and pressed it; modern mills spin it in a centrifuge (a decanter). Either way, the defining rule of virgin oil is that it is obtained by mechanical or physical means only — no solvents, no heat treatment that would alter the oil. What comes out is simply juice.
The phrases you see on labels follow from this. "Cold extraction" or "first cold press" legally means the oil was produced below about 27 °C; with modern centrifuges "press" is really a traditional turn of phrase, but the low temperature is real and worth having.
Not all olive juice is equal. Oils are graded by free acidity (a chemical measure of quality, expressed as % oleic acid) and by a trained tasting panel:
In short: only "extra virgin" guarantees flawless, mechanically extracted, low-acidity oil. Everything else is a step down. (Learn to judge it yourself in How to Taste Olive Oil.)
Autumn guests at Cortijo Bujio can see the harvest in the surrounding groves and visit a working almazara nearby — watching green olives become golden oil the same afternoon is unforgettable. (See olive oil around Montefrío.)
What does "extra virgin" actually mean? That the oil was extracted from olives by mechanical means only, has a free acidity of no more than 0.8%, and has no taste or aroma defects when assessed by a trained panel. It is the highest grade.
Why is early harvest better? Green, early-harvested olives yield less oil but produce oil with more aroma, more flavour and far more polyphenols — greener, more peppery and longer-lasting — which is why premium oils are usually early-harvest.
Does "cold pressed" matter? It means the oil was made below about 27 °C, which preserves aromas and antioxidants. With modern equipment it's more a traditional phrase than a distinct process, but low-temperature extraction is genuinely worth having.
What is the difference between "extra virgin" and plain "olive oil"? Extra virgin is pure, flawless mechanically extracted juice. Plain "olive oil" is mostly refined oil — heat- and chemically-treated to remove faults — with a little virgin oil added back for flavour, and far fewer antioxidants.
Cortijo Bujio is surrounded by working olive country. Read on: How to Taste Olive Oil, The Great Olive Varieties and Buying, Storing & Cooking with Olive Oil.
Sources: International Olive Council (grades & definitions); UC Davis Olive Center; Foods & Wines from Spain (ICEX).