Start With the Harvest Date, Not the Best-Before

Most bottles on a UK shelf carry a best-before date, and most shoppers treat it as the important one. It rarely is. Best-before is usually set two years from bottling, and bottling tells you very little about the olives inside. What you want to find is the harvest date — the moment the fruit was picked and pressed.

Olive oil is a fresh juice, not a wine that improves with age. Its green, grassy, almond-like aromas and that catch-at-the-back-of-the-throat pepper fade steadily from the day it is made. Northern Mediterranean harvests run roughly from late autumn through to January, so a bottle sold this spring should be marked with the most recent season. Look for a harvest date within the past twelve to eighteen months. If a label hides it entirely in favour of a vague best-before, that silence is information in itself.

What "Extra Virgin" Actually Means

The words on the front matter more than most people realise. Extra virgin means the oil was extracted from the fruit by mechanical means alone — pressing, spinning, centrifuge — without heat or chemical treatment, and that it meets strict chemical and sensory standards, including free acidity below around 0.8% and a passing grade from a tasting panel. It is the only category where the fruit's character is expected to survive into the bottle.

Virgin olive oil is made the same way but to looser standards. Plain olive oil — the unglamorous bottle with a plain label — is usually a blend of refined oil, which has been treated to strip out flavour and flaws, with a small proportion of virgin oil added back for character. It is reliable for roasting, mild to the point of anonymity, and perfectly honest for the price.

A few terms are worth translating. Light and mild describe flavour and colour, not calories — all olive oil contains roughly the same energy. Pomace oil is solvent-extracted from the leftover paste and belongs in industrial fryers. And cold extracted simply means the temperature stayed below about 27°C during processing, which is what you want.

Origin, Estate and the Wording That Matters

Next, ask where the olives were grown. There is a real difference between a blend of several countries, a single country, a named region, and a single estate or single grove. Estate wording signals traceability: one harvest, one press, one set of decisions, and often an earlier picking for a fresher, more bitter, more peppery oil.

Read the small print carefully. Packed in Italy tells you only where the bottling line stands. A bottle packed in one country may hold olives from Spain, Greece or Tunisia. Look instead for produced in, or a named region of origin such as Puglia, Crete, Kalamata or Jaén. If the label mentions a grove, a family name or a harvest month, that is usually a sign of a producer proud enough to be specific.

Dark Bottles, Tins and the Enemies of Freshness

Olive oil has two main adversaries: light and heat. Both accelerate the same staling process that turns bright oil waxy and flat. Dark glass, tinted glass and tins all offer protection; clear glass sitting under bright shop lighting does not. Where you have the choice, take the darker bottle.

Buy a size you will finish. A 500ml bottle used within a month will taste better throughout than a litre nursed for a year. At home, keep it in a cool, dark cupboard away from the hob, the oven and any sunny windowsill, and screw the cap down properly between uses. It will thicken in the fridge, which is harmless but inconvenient, so a cool cupboard is the better home. Once opened, aim to use a bottle within about six to eight weeks for peak aroma; it will not spoil after that, but it will quieten.

Tasting: What Bitterness and Pepper Tell You

You can judge a bottle in thirty seconds. Pour a teaspoon into a small glass, cradle it in your palm to warm it, cover the glass with your hand and smell. Fresh oil smells of cut grass, tomato leaf, green almond or artichoke. Then sip it, drawing air across your tongue as you would with wine.

Bitterness and a peppery sting in the throat are qualities, not faults. That pepper is a compound called oleocanthal, found in greatest concentration in early-harvest oils, and it fades fastest of all. Its absence is a warning. Flatness, a waxy or crayon-like note, a stale cardboard smell or a musty, fermented character all point to an old or badly stored bottle. Note, too, that the "acidity" on a lab report has nothing to do with the sourness of vinegar; free acidity is a chemical measure of the fruit's condition, not a taste you can detect.

A Practical Checklist for the Shop

Armed with the above, choosing a bottle becomes straightforward. Run through this before you reach the till:

• A clear harvest date, ideally from the most recent season and within twelve months.
• Extra virgin if flavour is what you are buying it for.
• The country or region of the olives, not just where it was packed, with single-estate wording a bonus.
• Dark glass or a tin, and a bottle free from dust or sun-faded labels.
• A size you will realistically finish in a couple of months.
• Mentions of early harvest or cold extraction, which usually indicate care.

Buy a bottle this autumn when the new season lands, taste it next to whatever is already in your cupboard, and you will never go back to shopping by best-before again.