Olive oils may be cloudy for several reasons:
If the EVOO is cloudy it may simply be unfiltered oil and what you are seeing is olive pulp that has not had time to settle. Over time, this pulp will settle to the bottom of the bottle. If it an unfiltered oil and the cloudy bottom is nothing to worry about. Of course, if it is filtered, it could be an indication of going or gone bad, but giving it a quick sip to figure that out.
If your oil has solidified during shipping in cold weather, allowing it rise to room temperature will generally clear up the cloudiness. If after coming up to room temperature there is still some residual discoloration, you may warm the oil in a warm temperature water bath to completely clarify it. Use caution and do not use hot water, as this could affect the quality of your oil. Your oil is not harmed by cold or freezing.
Cool temperatures cause the waxy esters in extra virgin olive oil to solidify. This often happens in the winter, in cool stores or after refrigeration. To return the olive oil to its clear state, place bottle in warm water leave the olive oil at room temperature.
We get many questions about freezing olive oil, such as: what are the clouds in my olive oil, will olive oil freeze in the refrigerator, is freezing olive oil good or bad for it, and does the way it freezes say anything about its quality? We have attempted to clarify the issues below.
Most manufacturers preset refrigerator temperatures to around 37°F. Chemistry texts list the freezing point of pure oleic acid at around 39°F. Olive oil manufacturers don’t generally list a freezing temperature because it is quite variable depending on the olive variety and ripeness of the olive at processing. Unlike the properties of an element or simple compound like water, olive oil is made up of hundreds of chemicals, many of which change with every extraction.
Like most fruit, olives have waxes on their epidermis (epicarp) to protect them from insects, desiccation, and the elements. These natural waxes are what allow an apple to be shined, for instance. If an oil is sent to a cold climate, or if it will be used in a product like salad dressing where it will be stored in the refrigerator, it is often “winterized” (chilled and filtered) to remove the waxes and stearates. A standard test to determine if olive oil has been sufficiently winterized is to put it in an ice water bath (32°F) for 5 hours. No clouding or crystals should occur.
CONGEALED AND PARTIALLY SOLID REFRIGERATED OLIVE OIL
Oil that has not been winterized will clump and form needle-like crystals at refrigerator temperatures as the longer chain fats and waxes in the oil congeal, but the oil will not usually harden completely unless chilled further. Some olive varieties form waxes that produce long thin crystals, others form waxes that congeal into rosettes, slimy clumps, clouds, a swirl of egg white like material, or white sediment that the consumer may fear represents spoilage. These visual imperfections also may form outside the refrigerator during the winter when oil is exposed to cold temperatures during transport. The white color in the hardened oil does not indicate spoilage.
Chilling or freezing olive oil does not harm it, and the oil will return to its normal consistency when it is warmed. The ideal temperature to store olive oil to reduce oxidation but to avoid clouding is around 50°F.