Olive Oil Health Primer: the Science Behind Cooking w/ EVOO

Liz Tagami, a friend who’s a specialty food and wine professional, recently alerted us to some misinformation about extra virgin olive oil published on a newspaper Web site. The article erroneously nixed the use of cooking with EVOO, calling it “fragile.” Several people soon posted comments disagreeing with the piece. The science backs their view.

A high-quality EVOO is quite resistant to heat. The “smoke point” at which a good EVOO begins to break down is about 410 degrees Fahrenheit, making it suitable for sautéing, roasting, frying and even deep frying.

Food science professors from the University of Bologna in Italy recently published an article entitled “The scientific truth on cooking with extra virgin olive oil.” The article goes into the chemistry of EVOO and concludes that “using extra virgin olive oils to cook is an excellent choice, both for the taste and for health” — provided you use a “high-quality, fresh” EVOO.

Here why EVOO’s chemistry makes it an excellent choice for cooking.

Olive oil is high in healthful monounsaturated fats. Chemically speaking, these are fats that have one double-bonded carbon in the molecule. By contrast, polyunsaturated fats — found in sunflower, corn, soybean, and flaxseed oils — have more than one double-bonded carbon. That makes these oils less stable, according to experts.

“The greater the number of double bonds in the fat’s fatty acids, the less stable the oil is. It’s more easily broken down by heat, light, and so on,” says Kathy McManus, director of the department of nutrition at Boston’s Brigham and Women’s Hospital.

Nutritionist Connie Guttersen also notes the antioxidants that come from the tocopherols and the polyphenolics in EVOO “contribute to the stability of the oil” as well as its “health promoting qualities.”

“Scientific studies suggest that a significant amount of the polyphenolics are heat stable and transferred to the food you are cooking,” including when you’re frying, adds Guttersen, an adjunct faculty member at the Culinary Institute of America’s campus in Napa Valley and author of The  Sonoma Diet (Meredith Books, 2005).

Polyphenols, by the way, are the chemical substances found in plants that may reduce the risk of heart disease and cancer. They’re natural antioxidants that fight against oxidation, and the oil’s breakdown.

And because it’s unrefined, says McManus, “extra virgin olive oil has the most polyphenols.”

Bon appétit,

Claude S. Weiller
Vice President of Sales & Marketing
California Olive Ranch