In a report released today, 69 per­cent of imported olive oil sam­ples and 10 per­cent of California olive oil sam­ples labeled as extra vir­gin failed to meet the IOC/USDA stan­dards for extra vir­gin olive oil.

Teams from the Australian Oils Research Laboratory in Wagga Wagga, New South Wales and the University of California at Davis Olive Center ana­lyzed 14 imported brands and five California brands of extra vir­gin olive oils from three dif­fer­ent regions of California.
See Also:UC Davis Report
The two lab­o­ra­to­ries eval­u­ated the oils based on stan­dards and test­ing meth­ods estab­lished by the International Olive Council (IOC) and United States Department of Agriculture (USDA), as well as sev­eral newer stan­dards and test­ing meth­ods adopted in Germany and Australia.

The tests found that sam­ples of imported olive oil labeled as ​“extra vir­gin” and sold at retail loca­tions in California usu­ally 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 per­cent of the cases.

The IOC and USDA chem­istry stan­dards often do not detect defec­tive olive oils that fail extra vir­gin sen­sory stan­dards. The report con­cluded IOC/USDA stan­dards would be more effec­tive in assess­ing and enforc­ing olive oil qual­ity by includ­ing another test referred to as the German/Australian DAGs stan­dards which were recently adopted in Germany and Australia to help detect the adul­ter­ation of extra vir­gin olive oils with refined olive oils. While the IOC/USDA chem­istry stan­dards con­firmed neg­a­tive sen­sory results in only 31 per­cent of cases, the German/Australian DAGs and PPP stan­dards sup­ported the neg­a­tive sen­sory find­ings in 86 per­cent of cases.

Of all imported olive oil brands tested only one, Kirkland Organic, was found to pass the sen­sory tests with all three regional sam­ples col­lected. As for the California brands just one, Bariani, exhib­ited sen­sory defects suf­fi­cient to fail extra vir­gin sen­sory stan­dards.

Just one sam­ple, from Safeway’s pri­vate label brand, had an acid­ity level above the .8% extra vir­gin thresh­old with a .84 read­ing, though other imported sam­ples came close to that. The FFA results for the California oils topped out with a .38 read­ing for Bariani. The low­est result of all olive oils tested was McEvoy Ranch Organic’s .16 level. Free fatty acid­ity is con­sid­ered a direct mea­sure of the qual­ity of the oil, the lower the num­ber, the bet­ter. Factors which lead to a high FFA in olive oil include fruit fly infes­ta­tion, delays between har­vest­ing and extrac­tion, fun­gal dis­eases in the fruit, and care­less extrac­tion meth­ods.

All sam­ples were within the IOC/USDA limit for per­ox­ide value (PV).

The 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 dam­aged and over­ripe olives, pro­cess­ing flaws, and/or improper oil stor­age.

See Also:UC Davis Report

• Report: Tests indi­cate that imported ​“extra virgin“olive oil often fails inter­na­tional and USDA stan­dards UC Davis Olive Center, July 2010