Myth – the Extra Virgin Olive Oil Fridge Test

An often perpetuated myth related to olive oil is the “Fridge Test” - a supposedly simple home test for olive oil authenticity. The myth is so widespread that you may even see conflicting versions of the test – some say your oil should solidify if it’s real, and others say it should not solidify if it’s real. If only it were that easy! This “test” unfortunately, is completely false and misleading. Read on to see why even the rumor-mongers are confused on this one.

Does the refrigerator test work for olive oil?

No. The refrigerator test is not a reliable way to determine whether olive oil is authentic or extra virgin. Authentic olive oils can either solidify or remain liquid in the refrigerator depending on their natural fatty acid composition, olive variety, growing conditions, and processing methods.

Food scientists and olive oil experts agree that there is no simple home test that can determine whether an olive oil is genuine.

What is the olive oil refrigerator test?

The "refrigerator test" (also called the fridge test) is a popular myth that claims you can determine whether olive oil is authentic by placing it in the refrigerator.

Unfortunately, there are even conflicting versions of the myth:

• Some claim real olive oil should solidify.
• Others claim real olive oil should stay liquid.

Neither claim is true.

Why does olive oil solidify in the refrigerator?

Olive oil solidifies because natural fats begin to crystallize at cold temperatures. This is a normal physical change and says nothing about whether the oil is authentic.

Extra virgin olive oil may become:

• Cloudy
• Thick
• Crystalized
• Completely solid

When the oil warms back to room temperature, it returns to its normal liquid state.

Why do some olive oils solidify while others don't?

Every olive oil has a unique natural composition. The temperature at which it becomes cloudy or solid depends on many factors, including:

• The olive variety
• Weather during the growing season
• Country and region of origin
• Harvest timing
• Processing methods
• Natural fatty acid profile
• Naturally occurring olive waxes
• Whether the oil has been filtered
• Whether the producer blended multiple olive varieties

Because these characteristics vary naturally, two authentic extra virgin olive oils can behave very differently in the refrigerator.

Can fake olive oil pass the refrigerator test?

Yes. An adulterated or blended oil may solidify in the refrigerator, while an authentic extra virgin olive oil may remain partially liquid.

Since many different edible oils contain fats that crystallize at cold temperatures, refrigeration cannot distinguish authentic olive oil from adulterated olive oil.

This is why olive oil experts do not recommend the refrigerator test.

Is it bad if olive oil solidifies?

No. It is perfectly normal for olive oil to become cloudy or solid when refrigerated.

Once the oil warms to room temperature, it will return to its normal appearance. A gentle shake is all that's needed before using it.

Is there a home test for olive oil authenticity?

No. There is no reliable home test for olive oil authenticity.

The only way to verify that an olive oil meets internationally recognized standards is through laboratory testing performed using established chemical and sensory methods.

If you're looking for confidence when purchasing olive oil, look for the NAOOA Quality Seal. Brands carrying the seal are independently tested at least twice each year to verify they meet internationally recognized quality and purity standards.

Rather than relying on refrigerator myths, buy olive oil from reputable brands, store it properly, and enjoy within 2 months of opening the bottle.

If you want confidence that your olive oil meets internationally recognized quality and purity standards, look for the “NAOOA Certified” Seal Olive Oils, which indicates the oil has been independently tested to verify it meets global quality and purity standards.