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We have an oil problem on our hands, and it has nothing to do with renewable energy and carbon emissions.

When experts convened recently at the 104th annual meeting of the American Oil Chemists’ Society, there was heated debate over what to do about olive oil. Even though concerns over poor quality, mislabeling and outright fraud surfaced a few years ago, olive oil continues to be plagued with credibility issues, even as it finds its way into more American homes and countries around the globe attempt to set quality-control standards. The state of extra-virgin olive oil — which is extracted from olives via mechanical means, not chemicals or heat — has been particularly controversial. While some industry insiders insist that stories of rampant adulteration are greatly exaggerated, others beg to differ.

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Among the conference participants was Dan Flynn, executive director of the Olive Center at the University of California at Davis, who a few years earlier had assessed the quality of extra-virgin olive oils in supermarkets based on standards set (but not enforced) by the U.N.-chartered International Olive Council as well as two additional chemical criteria. Shockingly, he found that 69% of imported olive-oil samples and 10% of California samples failed to meet sensory standards such as having more than zero fruitiness and not being rancid. Thirty-one percent were also deemed oxidized or of poor chemical quality. This year, Flynn followed up with more bad news. Among 15 samples of extra-virgin olive oil from restaurant suppliers, one was adulterated with canola oil, and a whopping 60% failed to reach sensory and chemical standards defined by the term extra-virgin.

Last spring, in the hope of improving matters, the USDA invited olive-oil brands to comply voluntarily with its Quality Monitoring Program. But so far only one company — Pompeian, the second largest olive-oil bottler in the U.S. — has chosen to participate. To do so, Pompeian officials say, they have had to greatly increase the size of their quality-control department, spending “several hundred thousand dollars” for staffing, training, research and record keeping.

Some industry groups argue that monitoring simply isn’t feasible. The vast majority of olive-oil brands in supermarkets come from companies that don’t own a single olive tree. They obtain the oil from middlemen, who don’t necessarily get it directly from the grower (or, in most cases, growers). With so many hands in the vat, it’s tough to know when and where adulteration or spoilage occurs unless there’s an inspection at every step of the way. And let’s not forget about the shippers and retailers involved before that bottle ends up in your pantry — even the best oils will deteriorate if left in a hot truck or near a sunny window.

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Then there is the problem that there are several certification programs besides the USDA’s and that test results can vary even when similar standards are used. Quality can change from year to year, from sample to sample. For example, even though Bertolli and 365 100% Italian both earned quality seals from the North American Olive Oil Association (NAOOA) and Pompeian earned USDA and NAOOA seals, 33% of the 45 samples tested from the three brands failed to meet chemical standards and 84% failed to meet sensory standards when assessed two years ago by UC Davis’ Olive Center. In another study performed a year later, the results for Pompeian and Bertolli were still not 100%, so competitors have questioned whether these products actually improved. But Eryn Balch of the NAOOA argues that taste can be subjective, changes over time and in this case has “nothing to do with adulteration.” She also claims that the reports out of UC Davis are funded by California olive-oil companies and that the panelists were partial to promoting domestic oils.

Flynn responds that the criticisms of the panelists are irrelevant, since they are professionally trained, and that fustiness and mustiness do not result from mishandling in shipping or storage but reflect the quality of the olives. Meanwhile, the California Olive Oil Council, which has its own seal program and requires local brands to participate, reports that the imported olive oils that it samples randomly from store shelves “come in at about 75% not extra-virgin grade.”

While we’re waiting (and waiting) for the various factions to stop pointing fingers and start working for the good of olive oil as a whole, remember this: as long as we keep thinking of olive oil as a shelf-stable condiment instead of the perishable product it is, someone might try to dupe us somewhere along the supply line — and we might not even know the difference. Fossil fuels may be more finite, but olive oil still has an expiration date.