Olive oil: How we test
International olive oil judge Judy Ridgway tastes our oils
The tasters
Our experts blind-tasted 12 standard extra virgin olive oils and rated the olive oils individually on aroma, taste, complexity and overall balance.
As a panel, they then graded the olive oils out of five to make our star ratings and find the best olive oils tested.
The gourmet olive oil experts were asked not to eat, drink coffee or smoke for at least 30 minutes before the tasting so that their palates were clean.
The oils were served in black glasses (the colour of the oil isn’t important for taste) at room temperature.
Palates were cleansed between tastings with water and fresh apple slices.
The experts were:
Adam Byatt Head chef and owner of Trinity – Good Food Guide restaurant
Judy Ridgway International olive oil judge and author
Sam Rosen-Nash Savoury grocery buyer at Fortnum & Mason
James Wierzelewski Executive chef at Harrods
The oils
We tested standard supermarket and branded extra virgin oils from: Aldi, Asda, Bertolli Originale, Carapelli, Felippo Berio, Lidl, M&S, Morrison’s, Napolina, Sainsbury’s, Tesco and Waitrose. We tried to buy 500ml bottles but, where unavailable, we bought 750ml bottles.
Virgin oils are produced by mechanical or physical methods only, such as washing, decanting and filtration.
Chemical processes can be used with standard oils, which can alter aroma and taste. Advances in production mean that terms such as first and second press are less relevant – extra virgin and virgin oils are both from first presses.
Extra virgin olive oil is the highest quality and has an acidity level of no more than 0.8%, for virgin oil it’s no more than 2%. Extra virgin olive oil tends to have a stronger flavour and is generally used as a dressing as it’s the most expensive type.
Money saver
If you’re cooking with olive oil, chef Adam Byatt says that it’s not worth using extra virgin oil – it’s costly and the strong taste can overpower delicate food.
We say try standard olive oil. For example, while the Sainsbury's extra virgin oil we tested cost 54p per 100ml, its standard olive oil cost 40p per 100ml, saving you 70p per bottle.