Olive oil never improves with age. Unlike wine, to which it is often compared, it has nothing to gain from aging. Each passing month takes something away from it: aromas, polyphenols, a part of what made it interesting.
Choosing an olive oil therefore means choosing the freshest possible. Here's how to do it.
Green fruity, ripe fruity, black fruity
In France, AFIDOL, the olive interprofessional organization, distinguishes three taste families. They do not describe a superior or inferior quality, but different profiles, linked to the harvesting time and the treatment of the olives before milling.
Green fruity
Olives are picked early in the season, usually from October, before their full maturity.
The aromas are herbaceous, vegetal: artichoke, cut grass, tomato leaf, fresh almond. In the mouth, the bitterness is frank and the pungency, this peppery sensation at the back of the throat, is marked.
This is by far the richest profile in polyphenols. Early harvesting is the main lever for phenolic concentration. It also best reflects the freshness of the olives at the time of milling.
Ripe fruity
Olives are harvested later, at maturity, from November to December. They are milled immediately after picking, as for green fruity.
The aromas evolve towards ripe fruits: apple, almond, red berries, floral notes. Herbaceous aromas are almost absent. Bitterness and pungency become subtle to medium.
This is a rounder, more accessible profile, often appreciated by those who find the green fruity too powerful. The aromatic richness remains great, but the polyphenol content is lower.
A useful nuance: these appellations do not necessarily reflect the color of the olives. A green fruity is not necessarily made from green olives, nor a ripe fruity from black olives. The variety plays as much as the harvest date, some cultivars retain a marked bitterness even when harvested late.
Black fruity
Also called "old-fashioned taste," it is based on a different process. The olives, harvested late, are not milled immediately. They are stored for a few days anaerobically, at controlled temperature, to undergo controlled fermentation.
The aromas are reminiscent of candied black olives, cocoa, sometimes vanilla. There are no fresh fruit or vegetal notes left. Bitterness and pungency are almost absent.
This is an ancient Provençal tradition, and a profile that some specifically seek out. But it should be known that fermentation increases free acidity: a black fruity oil is generally classified as "virgin" and not "extra virgin." And the process, by definition, does not preserve polyphenols.
What "extra virgin" means
This is the only designation that guarantees both the process and the sensory quality.
It requires exclusively mechanical extraction, no chemical treatment, a free acidity of less than 0.8 g per 100 g, and the absence of any defect during tasting. Extra virgin olive oil is also the only oil whose extraction temperature is regulated, with a maximum of 27°C.
Olive oil categories:
| Category | Maximum free acidity |
|---|---|
| Extra virgin | 0.8% |
| Virgin | 2.0% |
| Ordinary virgin | 3.3% |
Polyphenols, freshness markers
A third indicator deserves attention, more rarely displayed but decisive.
Polyphenols are defense molecules produced by the olive tree against stress, UV, and infections. When ingested, they help neutralize free radicals and reduce inflammation.
They have a recognizable sensory signature: oleocanthal causes this peppery sensation at the back of the throat, oleuropein causes bitterness. These characteristics, often perceived as defects, are actually evidence of phenolic richness.
A mild, round olive oil without bitterness or pungency is almost always poor in polyphenols.
Three factors determine their content: the olive variety, the earliness of the harvest, and temperature control during extraction. A fourth factor, often overlooked, is added to this: storage conditions.
European regulation 432/2012 authorizes a health claim on olive oil polyphenols, provided that it contains at least 5 mg of hydroxytyrosol and derivatives per 20 g of oil. This is a useful benchmark: a brand that claims this claim has had its oil analyzed.
How to spot freshness on the shelf
Harvest date
This is the most important information, and the most often missing.
A best before date says nothing. It is set by the producer, generally between eighteen and twenty-four months after bottling, with no direct link to the actual state of the oil.
The harvest date, on the other hand, says everything. An oil from the current season is incomparably richer than an oil from two previous seasons, even if stored in good conditions.
A producer who displays it assumes the traceability of their vintage. A bottler who does not display it rarely has an interest in it being known.
The container
Light triggers photo-oxidation, which degrades unsaturated fatty acids, polyphenols, and tocopherols.
Transparent glass offers no protection. Dark, tinted, or opaque glass provides real protection.
A quality oil sold in a clear bottle placed under a supermarket neon light will have lost some of its active ingredients long before reaching the kitchen.
Origin
A precise origin, region, mill, is a sign of assumed traceability.
Conversely, the mention "blend of olive oils originating from the European Union" indicates a blend of multiple provenances, difficult to trace, generally selected on cost criteria.
Color
Useful counterpoint: color says almost nothing about quality. It depends on the variety and maturity. Professional tasters work in opaque blue glasses, precisely so as not to be influenced by it.
Tasting an olive oil
Three positive attributes are sought in professional tasting.
Fruity: all perceived aromas, by direct and retronasal pathways. Its intensity can be light, medium, or intense.
Bitterness: perceived in the middle of the mouth, linked to oleuropein.
Pungency: this peppery sensation at the back of the throat, linked to oleocanthal. It appears a few seconds after tasting, and often causes coughing.
An extra virgin oil must present these three attributes, at varying intensities, and no defects.
Storing fresh oil
The best purchase does not survive poor storage.
Away from light. Store it in a closed cupboard, away from any light source.
Away from heat. Avoid placing it near hobs or the oven. Heat accelerates oxidation.
Tightly closed. Contact with air is the main vector of oxidation once the bottle is opened.
In a small format. An oil rich in polyphenols consumed in a few weeks is better than a large format started for months.