Olive oil isn't like wine. It doesn't improve in the bottle. It's the juice of a fruit, and from the day it's pressed it slowly loses its aroma, its colour and the bitter, peppery bite that makes good oil worth buying. A great oil that has sat on a shelf for two years can taste flat, and one that's been kept badly can taste stale.
The good news is that freshness is easy to check once you know where to look.
1. Look for the harvest date, not just the best-before date
Most bottles only carry a best-before date, and that date is usually set 18 to 24 months from bottling, not from harvest. Oil can sit in a tank for months before it's bottled, so a best-before date tells you surprisingly little.
A harvest date tells you much more. In the northern hemisphere, olives are picked between October and December, so in winter 2026 the freshest oil you can buy says "harvest 2026" or "2026/27". If a producer doesn't print a harvest date, it's fair to ask why.
2. Check the container
Light, heat and air are what age olive oil. Good producers protect it with:
- Dark glass (green or brown), which blocks most light.
- Tins, which block light completely.
- Bag-in-box, which blocks light and also keeps air out after opening, because the bag folds in as you pour.
Clear glass looks lovely on a supermarket shelf under bright lights, which is exactly the problem.
3. Smell it
Pour a little into a small glass, cup it in your hand for a minute to warm it, then smell. Fresh extra virgin olive oil smells green and alive: cut grass, green apple, tomato leaf, artichoke, green almond.
Tired or faulty oil smells of something else:
- Rancid: crayons, putty or old nuts. The oil has oxidised.
- Fusty or muddy: olives that sat too long before pressing and started to ferment.
- Winey or vinegary: another fermentation fault.
- Nothing much at all: often a sign of age.
4. Taste it
Take a small sip, draw some air in through your teeth, and let it reach the back of your throat. Fresh, high-quality oil has three things the official tasting panels look for: fruitiness, bitterness and pungency, the peppery catch in the throat that can make you cough.
That bitterness and pepper come from natural polyphenols, and they fade as oil ages. If an oil is completely smooth and mild, it may be a gentle variety, but it may also simply be old. (We explain more in why good olive oil is bitter and peppery.)
5. Be wary of very low prices
Picking olives at the right moment, pressing them quickly and storing the oil properly all cost money. Very cheap "extra virgin" oil isn't necessarily fake, but it's often older, blended from several harvests and countries, or from overripe fruit.
Once you've bought it
Freshness also depends on you. Keep oil somewhere cool and dark, away from the cooker, and use an opened bottle within a couple of months. Our guide to storing olive oil has the details.
How we do it at 1540
Every batch of our oil carries its harvest year. Our 2026 oil was first pressed on 5 October 2026 from our own organic Moraiolo olives in Umbria, and it ships in dark glass or bag-in-box. It's as fresh as olive oil gets: bright green, grassy and properly peppery.