Why has my olive oil gone cloudy?

Unless you've been living in a cave, or perhaps especially if you've been living in a cave, you'll have noticed that it's been a bit chilly of late.

Being constantly surrounded by the cold, white stuff got us thinking, and we thought we'd take the opportunity to answer a few oft-asked questions regarding olive oil and the cold.


Why has my olive oil gone cloudy?
Cloudy olive oil means that the oil is frozen, or in the process of becoming frozen. This is perfectly normal and can occur anywhere from around 10°C (50°F).

The ‘freezing point’ of olive oil is not very well defined, (unlike water for example), because it has such a complex chemical structure. This structure varies depending on the olive varietal(s), their ripeness, and the process undertaken to produce the oil.

These variations mean that olive oil can begin to freeze at a range of temperatures. The freezing process itself is also a lot slower. Whilst an olive oil may start to solidify at say, 7°C / 45°F, it may not freeze completely until it reaches -6°C / 21°F.


Can I still use olive oil after it has been frozen?
Yes, the quality of the olive oil won’t be affected at all. Just let it slowly come to room temperature and it will return to its normal state.


So can I keep my olive oil in the fridge?
Certainly if the choice is between a hot kitchen and a fridge, you’d be wise to go with the latter. The ideal temperature is about 14°C / 57°F, which could be a larder, cellar or even a cool garage. However the oil should be fine at around 21°C / 70°F provided it is kept away from heat sources like ovens or radiators.

Bear in mind that whilst freezing/refrigerating your oil won’t damage it, constantly freezing, thawing and re-freezing it may well do, so you might want to split the oil up and defrost it as needed. (Some people use ice-cube trays!) Olive oil also expands by about 4% when frozen, so make sure you leave it a little bit of space.


Will freezing olive oil preserve it or prolong its lifespan?
Freezing olive oil will almost certainly ‘stall’ its deterioration, and retain the flavour, aroma and beneficial properties of the oil at the time of freezing. For exactly how long it can stay in this condition for remains a mystery…if anyone discovers the answer, please let us know!


Is the way the olive oil freezes an indicator of quality?
We found an interesting article by Cheeseslave that suggests this is the case. However, it is possible to remove waxes and other substances from olive oil so that it remains a fluid at lower temperatures. The jury is still out on this one…


Can I eat frozen olive oil?
Most definitely! We leave you with some great examples we found of olive oil being used in this imaginative way.


Ciao!
Emily and Paolo

Tomato, watermelon, frozen olive oil chips. Courtesy of 50 Yen on Flickr.



Elderflower parfait, frozen olive oil emulsion. Lovely stuff by Dale at The Components.



Frozen olive oil (We suspect that this is oil encased in a solid 'skin', rather than actual frozen oil- nice concept though!) Minibar in Washington. Thanks to kiat.net!


Cannelloni of marinated goose liver with orange and juniper berry; praline of goose liver and chocolate with mango and frozen olive oil; sauteed goose liver with yuzu, ginger and hazelnut. Thanks to Brit and Armand for this one.