Most avocado oil is rancid or impure, experts warn

Avocado oil — often hyped as a light, heart-healthy oil — usually has a dark, greasy background.

A study from the University of California at Davis found that a whopping 69% of avocado oils sold by retailers had impurities such as cheaper oils mixed in.

Additionally, many of the store-brand avocado oils had high levels of oxidation, indicating that the oils had started to turn rancid.

Out of 29 refined avocado oil samples, only three met basic quality and purity standards, the study authors wrote in the journal Food Control.

And it didn’t matter if consumers bought expensive avocado oils or low-cost store brands.


Avocado oil, honey, olive oil and other agricultural products should be screened for impurities, food experts say.
Avocado oil, honey, olive oil and other agriculture products should be screened for impurities, food experts say.
Getty Images/iStockphoto

“We found that low-cost products indicate a higher probability for adulteration, but high cost didn’t guarantee purity or quality,” Selina Wang, an associate professor in the Food Science and Technology department at UC Davis, said in a statement Wednesday.

Common impurities that were added to avocado oil included sunflower oil, safflower oil, canola oil and soybean oil, the study authors said.

Avocado oil has risen in popularity in recent years due to its light, buttery flavor and numerous health benefits. Like olive oil, it’s rich in oleic acid, a healthy, monounsaturated omega-9 fatty acid, according to Healthline.

And in addition to being easy to cook with — it has a high heat point and doesn’t burn easily — it’s also rich in anti-oxidants and vitamins A and E, and might help to lower cholesterol levels and ease high blood pressure.

But the findings of the UC Davis survey highlight the need for additional safeguards and quality standards to ensure that consumers are getting what they’re paying for.

“This study demonstrates that although progress is being made in standard development … there are still issues with purity in avocado oil and these issues extend significantly into private-label oils,” Wang said.

Unfortunately, this isn’t the first time in recent years that food manufacturers have been criticized for selling food that isn’t pure, or even safe for consumers.

Honey manufacturers from China have been slammed by the European Union for “honey laundering,” or selling honey that contains sugary syrups, artificial coloring, water — and, in some cases, lead and other unsafe heavy metals.

“It’s basically sugar water,” one EU official told the Financial Times, and it drives honey prices down so low that honest European honey makers can’t compete.

So last month, EU officials proposed tough new labeling standards to fight the influx of cheap, impure honey from outside the bloc.


A farmer holding a ripe avocado.
“We found that low-cost products indicate a higher probability for adulteration, but high cost didn’t guarantee purity or quality,” said Selina Wang, an associate professor in UC Davis’ Food Science and Technology department.
AFP via Getty Images

Olive oil, too, has been the subject of numerous recent investigations. Thousands of tons of cheap, low-grade olive oils from Spain and Greece were marketed as expensive “extra-virgin Italian” olive oil, a 2018 investigation revealed.

“America is the dumping ground of all those fraudulent operations,” one olive oil expert told Forbes. “There are not enough resources to control the over 350,000 tons of olive oil entering the country. That’s why, even after the scandals, adulterated olive oil bottles are still on supermarket shelves.”

Wang hopes the avocado oil study’s findings will help establish standards to benefit consumers as well as the avocado oil producers who want to compete in a fair market.

“I’m very optimistic for the future of the avocado oil industry,” Wang said. “It’s a high-value product with high consumer demand, similar to what I saw with olive oil 10 years ago. Olive oil quality and purity have improved significantly, which is where I see avocado oil going, if we can establish fair standards and eliminate fraudulent products.”