How to Avoid Buying Rancid Olive Oil

By Danielle Centoni

January 23, 2021

Extra-virgin olive oil is one of the healthiest, tastiest, and most versatile oils available. It’s bursting with antioxidant-rich polyphenols, which have been linked to all sorts of health benefits from lower blood pressure to reduced risk of depression. And its flavor — sometimes mild and buttery, other times robust and bitter — adds a new dimension to everything from soups and salads to sauces, sautées, and more.

But that’s only if you’re buying the highest-quality extra-virgin olive oil. And the simplest way to do so is to look for extra-virgin olive oil that’s made in California.

Thanks to the California Olive Oil Council, California extra-virgin olive oil has the most rigorous standards for quality in the world.

What Is the California Olive Oil Council?

Established in 1992, the California Olive Oil Council (COOC) is an association of over 300 growers and producers, providers, retailers, and supporters of the California olive oil industry. For nearly two decades, the COOC has been committed to upholding the highest standards within the olive oil industry through their Seal Certification Program.

Following every harvest, COOC members must submit their oils to an independent laboratory for a chemical assessment (which they must pass). They must then submit that same oil to the COOC Taste Panel for a sensory assessment. This is because certain defects can only be detected by the human palette.

Only oils that pass both assessments earn the right to use the seal. If a bottle of olive oil carries the COOC Seal, you can be sure the oil you are buying is 100% extra virgin olive oil made from 100% California grown olives.

In other words, if you’re looking for high-quality, great-tasting olive oil, the California Olive Oil Council Seal is a great place to start.

What Else to Look for When Buying Olive Oil

You’ll also want to look for oil in dark glass bottles or tins, rather than clear glass bottles. Exposure to light, including bright store lights, can dramatically shorten the shelf life of the oil. And you should look for the most recent harvest date. In California, that’s in October, November, and December. Note that not all olive oils have the harvest date on the bottle, but the best-quality oils will, indicating just how fresh the oil is.

Beyond the seal, the type of bottle or tin, and the harvest date, it’s really a matter of personal preference. If you’d like to explore your options, check out Market Hall Foods. The specialty food store in Oakland, California has championed California extra-virgin olive oils for the last 30 years — or right around the time that the first wave of growers and producers were getting started in the state. They sell incredible olive oils from around the world, and only sell extra-virgin olive oils from California that are COOC- certified.

One of our favorite producers, which can be found at Market Hall, is Séka Hills. The only tribal nation producing olive oil, they are deeply committed to sustainable practices and rigorous production standards that help to preserve the polyphenols. They produce a tribal blend olive oil, as well as single-varietal olive oils. Arbequina is known for its mild, buttery flavor, Picual olive oil tends to be fruity and slightly sweet, and Frantoio has green, grassy notes, and a nutty quality. Use promo code CLEANPLATES for 10% off online orders over $75 until March 31.

Photo Credit: Alex Lau / Bon Appetit

How to Store and Use Olive Oil

Extra-virgin olive oil is a fresh juice and once opened, the oil will begin to oxidize. Use it generously and often and try to consume it within 2 -3 months to prevent the oil from going rancid. If it starts to smell like nuts, it’s rancid.

Get cooking!