Your Imported Olive Oil Is No Longer A Virgin

Before you reach for that fancy-looking, Italian-sounding bottle of olive oil at the supermarket, under the assumption that “it’s from Italy, they must know what they are doing”, first consider this:

Researchers at the UC Davis Olive Center (which actually exists, and is part of the “Robert Mondavi Institute For Wine and Food Science”) recently concluded that a high percentage of imported “extra virgin” olive oil fails international and USDA standards.  In other words, it is sold at the higher grade of “extra virgin” (and priced accordingly) when in fact it is a lesser grade (merely “virgin”).

“Extra virgin” is the top grade of olive oil, and is determined based on standards set forth by the International Olive Council (IOC) and the USDA.  The standard is defined both by chemical standards and “sensory standards” (i.e. taste)- the oil “must have zero defects and greater than zero fruitiness.”

The UC Davis research team tested 14 imported brands and five California brands of oil sold as “extra virgin olive oil.”  For the imported oils, three bottles of each were purchased in supermarkets in Sacramento, Los Angeles and San Francisco.  For the local oils, three bottles were purchased in each of Sacramento and San Francisco.  The team used a number of chemical testing methods, designed to detect indicators of hydolyzed, oxidized or otherwise poor quality oil, to detect the presence of adulteration of the oil with other, lower quality (cheaper) oils, as well as a sensory test for taste, odor and mouthfeel.

The team concluded that:

Our laboratory tests found that samples of imported olive oil labeled as “extra virgin” and sold at retail locations in California often did not meet international and US standards.  Sensory tests showed that these failed samples had defective flavors such as rancid, fusty and musty.  Negative sensory results were confirmed by chemical data in 86% of the cases.  Our chemical testing indicated that the samples failed extra virgin standards for reasons that include one or more of the following:

• oxidation by exposure to elevated temperatures, light and/or aging;

• adulteration with cheaper refined olive oil;

• poor quality oil made from damages and overripe olives, processing flaws, and/or improper oil storage

Specifically, the team found that 69% of the imported olive oils and 10% of the California olive oils failed to meet IOC/USDA standards for extra virgin olive oil.  Of the imported samples, 83% also failed German/Australian standards , and two samples that met IOC/USDA standards failed German/Australian standards.

The data strongly suggests that some imported olive oil producers are watering down their extra virgin olive oil with cheaper oils, and using subpar olives and techniques in the production process, among other things.

So – the question is, which oils are bona fide “extra virgin,” and which aren’t?  The published study results can be found here, so you can see for yourself if you are curious (it is only 10 pages).   Suffice to say that there are some brands on there that come as a bit of a surprise (Newman’s Own – say it isn’t so! Whole Foods, how could you?).  Also I checked my my own cupboard and I am embarrassed to report that my own (Italian-sounding) olive oil does not have a good track record.

In conclusion: if you rely heavily on extra-virgin olive oil, particularly in things like salad dressings, or drizzled over stuff – you may have a particular interest in reading the study, and you may find yourself with newfound suspicion and caution then next time you venture into the “oil n’ vinegar” aisle of your favorite supermarket.  But honestly, just give it a taste – if it tastes good to you, then its probably just fine.  If not, go back to the supermarket, throw a copy of this study in their face and demand your money back.