Product knowledge
What Does Olive Oil Acidity Actually Mean?
Olive oil acidity is a lab measurement of free fatty acids in the oil, expressed as a percentage, and it's the single number that separates extra virgin from every grade below it — extra virgin must sit at or under roughly 0.8% free acidity, with virgin oil allowed up to about 2%. It has nothing to do with how sharp or sour an oil tastes on the tongue; acidity in this sense can't be tasted, only measured.
That distinction — a chemical test rather than a flavour note — trips up plenty of buyers who assume a 'low-acid' oil should taste milder or a 'high-acid' oil should taste sharper. Neither assumption holds, which is exactly why acidity sits alongside, not in place of, the sensory checks that actually predict how an oil performs on the table.
Free fatty acids, in plain terms
Fresh, undamaged olive oil is made almost entirely of triglycerides — fat molecules with their fatty acid chains still bonded together. Bruised, overripe or poorly stored olives, and oil that's been mishandled after pressing, start breaking some of those bonds apart, releasing individual free fatty acids into the oil. The acidity percentage simply measures how many of those broken-apart, "free" fatty acids are present relative to the total fat — a lower number means fewer broken bonds, which generally tracks with fresher, better-handled fruit and oil.
Why acidity is measured in a lab, not tasted
This is the part that trips people up: free fatty acid levels don't register on the tongue at all. A technically low-acidity oil can still taste flat or stale if it's oxidised, and a slightly higher-acidity oil can taste vivid and fresh if it's otherwise well made — acidity and flavour are checked by completely different tests. Grading an oil on acidity is a lab exercise, titration against a base solution; grading it on taste is a separate sensory-panel exercise, and official extra virgin certification requires passing both.
What the acidity threshold actually tells a buyer
In practice, acidity works as a proxy for how the fruit was handled before pressing — bruised or long-stored olives before milling tend to push acidity up, which is part of why a same-day or fast-turnaround press is prized. It's a useful quality signal, but only one of several; the full grading picture, including how acidity fits alongside the refined, pure and lampante categories below virgin, is covered in what olive oil grade names actually mean.
Where this fits into judging a bottle
Acidity numbers rarely appear on retail labels in Canada, since the grade name itself — extra virgin, virgin — already certifies the oil falls under the relevant threshold. For a buyer, the more useful day-to-day checks are the ones covered in how to judge a good extra virgin olive oil: harvest date, aroma and taste, with acidity sitting in the background as the technical line that keeps a bottle honestly labelled extra virgin in the first place. Lio Premium Virgin Olive Oil is graded and labelled to that standard.
Related questions
Can you taste the acidity level in olive oil?
No. Free fatty acid levels are a lab measurement with no direct flavour signature — a low-acidity oil can still taste stale, and a fresh, vivid-tasting oil isn't proof of low acidity on its own.
What acidity level counts as extra virgin olive oil?
Extra virgin sits at or under roughly 0.8% free fatty acidity, with virgin oil permitted up to about 2% — the tighter threshold is one of the tests a bottle must pass to legitimately carry the extra virgin name.
Does higher acidity mean lower quality olive oil?
Generally, yes, as a proxy — higher free fatty acid levels usually track with bruised, overripe or poorly handled fruit before pressing, which is why acidity is one of the tests behind the grade names.