A group of California chefs are taking on the olive oil industry after a recent University of California Davis study showed that as many as 69 percent of brands tested were not true extra virgin olive oil. On behalf of the chefs, an Orange County Calif. law firm, Callahan & Blaine filed a class action suit against distributors and retailers of extra virgin olive oil for misleading and defrauding California customers.

The defendants include brands such as Bertolli, Filippo Berio, Carapelli, Star, Colavita, Mezzetta, Pompeian, Rachael Ray, Mazola and Safeway Select. Also included in the suit are retailers and supermarkets including Bristol Farms, Gelson's Markets, Vons/Pavilions, Ralphs, Stater Brothers, Albertson's Market, Target, WalMart, KMart and Nob Hill Foods.

The UC Davis study revealed that a majority of the brands were old, poorly made and/or adulterated. “Before this study, we had anecdotal reports of poor quality olive oil being sold as extra virgin but now we have empirical proof,” said Dan Flynn, executive director of the Olive Center at UC Davis. The University of California, Davis Olive Oil Chemistry Laboratory collaborated with the Australian Oils Research Laboratory, the California Olive Oil Council, the American Oil Chemists' Society (AOCS) and the Australian Olive Oil Association to test the oils.

The North American Olive Oil Association, which represents most of the importers, and the International Olive Oil Association denounced the study. “Of the olive oil sold in stores throughout the U.S. tested by the NAOOA, on average approximately 99 percent meets the internationally recognized and science-based IOC standards,” said Bob Bauer, president of the NAOOA, in a statement. “Our testing represents a true picture of what American consumers buy in grocery and specialty stores.” Bauer and the IOC do not agree with the type of testing used in the UC Davis study.

The UC Davis study showed that some of the oils were adulterated with other types of oil, which presents a food safety issue. If olive oil is blended with other types of oil without the consumer’s knowledge, this could present serious allergy issues. “When different types of oils are blended, but sold as extra-virgin olive oil, it creates a Russian roulette for consumers,” said Patty Darragh, executive director of the California Olive Oil Council, “because there is no traceability to identify the source of the adulterated oil.” Darragh warns retailers not to place their private label on just any oil; otherwise the store could be held accountable for selling fraudulent products. Darragh recommends that retailers purchase only extra-virgin olive oil that has undergone testing and has quality-assurance guarantee attached to the product.