Rich Table event photo 3
Olive oil attributes include fruitiness and pungency. Photo: Alison Altomari

In a small warehouse in West Berkeley, a group of experts meets two to four times a month to “swirl, sniff, slurp, and swallow.” The sensory taste panel is evaluating bottles of newly milled oils for the California Olive Oil Council, a trade association which has been based in the city since 1997.

The goal is to certify the California oils as genuine extra-virgin quality products. By the end of this tasting season, the group will have tested around 350 different oils.

These 24 astute tasters have been trained to pick out even the most minute and subtle defects (think: fermented and musty flavors) and attributes, like fruitiness and pungency, in each olive oil. In order to gain a COOC seal of approval, oils must be both defect-free and have a harmonious balance of positive attributes. And, despite what sounds like a test subject to the whims of human taste, the panel has proven to be reliable.

“The reason for the sensory [tasting] is that there is no good lab test that will come up with those attributes. So the humans, with their flaws, are the best tools,” said Nancy Ash, a taste panel leader.

With approximately 2.4 million gallons of olive oil produced between the months of October and January of this past year, it was another banner year for California extra-virgin olive oil. Not only has this bumper crop kept our shelves bursting with local oils, but it has also kept the California Olive Oil Council (COOC) quite busy.

The California Olive Oil Council has been based in Berkeley since 1997

The COOC was founded in 1992 by a group of devoted olive oil producers looking to educate the public about the merits of local extra-virgin olive oil. As Patty Darragh, the executive director of the COOC, explains, Americans were just starting to use olive oil in everyday cooking at the time of its founding. Few consumers knew, or cared to learn, how to find the good stuff. Even if they did, it was difficult to know what to look for on a bottle of oil. Unlike in Europe, the U.S. had no real standards for labeling oils, instead relying on generic terms like “fancy” and “extra-fancy.” Frustrated by this subpar labeling, the COOC expanded its agenda in the late 1990s in order to develop its own set of guidelines.

The COOC adopted a two-prong certification method based on the European model used by the International Olive Council (IOC). First, the oil goes through chemical tests that examine whether or not oils meet set criteria for purity (they must contain only olive-based oils) and quality (they must be under specific limits for free-fatty acids and peroxides).

However, as Darragh explains, “the chemical testing is just one component to us. The most important component is having our panel taste the oil in a blind setting … because the chemistry tests are just strictly indicators of the quality of an olive oil.”

The COOC taste panel convenes on Thursday mornings in the second floor of the COOC office. It’s a starkly lit room filled with plastic folding tables and chairs. Walking into the space felt much like stepping into an SAT or GRE exam room. No romance, no luster, all business. But, I thought, at least there are twelve excellent oils sitting in the back of the room instead of stacks of exam packets and scantron sheets.

The oils are tasted blind, so before any panelists arrive, the COOC’s marketing director pours each sample into its own small blue glass, labels each with a letter code, and places them on heating blankets. Next to the samples are bottles of sparkling water and a bowl of ice-cold Granny Smith apple slices. Each of these elements is important: the blue glasses obscure the color of the oils so that tasters are not swayed by particularly green samples, the heating pads keep the oils at the optimum temperature (around 84 degrees) for tasting, and the water and apples are key for cleansing the palate after each sample.

“This is done worldwide. … I could walk in to a panel in another country, not speak the language, and participate on their panel. Because we’ve all had the same training [and] we all have the same process where you taste an oil, you score it, you take your break with apples in between,” said Ash.

Lone Oak
Lone Oak olive oil: one of the COOC’s 2013 award winners

Once all of the panelists arrive and pull out their computers — tasting notes are recorded online so that the statistical analysis (more on this later) can be run instantly — we grab our first oil samples. Most of the panelists set up giant white blinders around their station before they begin to taste in order to keep their scores as neutral as possible. I’m sitting next to Nancy, who is walking me through the steps for tasting, so I don’t put up a blinder.

First, I gently cup the glass of oil in my hand and swirl it gently. I stick my nose into the glass and inhale deeply. Just like tasting wine, swirling the glass helps to release the aromas in the oil. I think I detect whiffs of grass and, um, olives. I sniff a few more times — maybe there’s some eucalyptus in there as well.

After sniff comes slurp, the most humorous of the tasting steps. Instead of simply gulping down the oil, we take a bit of oil in the front of our mouths and suck in a couple of short bursts of air. Yes, it sounds funny, and it feels even funnier. But slurping and sucking is an important step in tasting oil. As Ash explains, the mouth and nose identifies different flavor components (or aromas) in different locations. Spreading the oil all around the mouth makes it possible for tasters to look for multiple aromas at once. Depending on the part of the mouth and nose, “we get different parts of the defects and the positive fruitiness,” said Ash.

Even after a few attempts, I discover that I am not very good at slurping. Much of the oil just ends up getting sucked right back into the back of my throat. Luckily, swallowing the oil is the final step in tasting, so at least I’m getting something right. This step is all about evaluating an oil’s pungency. Pungency is most often recognized as the sharp flavors that cause coughing and a bit of burn when the oil is swallowed. A good olive oil will have some amount of pungency; depending on the time of harvest and milling, it will be more or less mellow.

Now that I’ve swirled, sniffed, slurped, and swallowed, I turn to my computer to input my evaluation. Scores are recorded on a scale of 0 to 10. But instead of simply choosing a number, tasters use a sliding scale to indicate their score by clicking on a line graph. The scoring is intended to be instinctual, so there are no numbers listed on the graph. Each taster’s number scores, as well as the group’s median and average scores, are revealed once the tasting is complete. According to Ash, this process takes “the individual experience and, by comparing it to the others in the group, makes it scientific.”

My first task is to identify defects. Oil defects are tastes that indicate olive spoilage and come with onomatopoeic titles like “fusty” and “musty.” Says Ash, “All fruit starts out good. And then something happens to it.” Most of these problems result from mistreatment of the fruit during and immediately after harvest. “When an olive is on a tree, the tree and the root system act like an umbilical cord, basically. It feeds the olives. The second the olive is detached from that, it starts to degrade,” she said. This means that extra-virgin oils must be milled as soon after harvesting as possible.

Oils can develop defects as a result of anything from the presence of mold spores on the olives to the oxidization that happens when sitting on a shelf for too long before use. In other words, it seems pretty easy to make bad olive oil. Yet California seems to do a pretty good job— in the last few years only “about 3-4% do not make extra-virgin grade” said Darragh.

The criterion for extra-virgin oil is not just an absence of defects. Good oils also need to possess a balance of the three main positive attributes: fruity, bitterness, and pungency. Each of these elements is also evaluated on the blind sliding scale.

Clicking on graphs isn’t too hard, and I breeze through these first couple of pages. Then comes the descriptive analysis. Here’s where I get stuck. On this page is a long list of flavor attributes — things like grass, banana, cherry, and walnut shell — that tasters are trained to recognize in the oils. We are supposed to rate them as low, medium, or high. I do my best, but seem to find that each oil tastes like olives, grass, and sometimes pine.

Rich Table event photo 1
California oil oils were tasted recently at an event at Rich Table in San Francisco. Photo: Alison Altomari

But according to Ash, I am not alone in my struggle to accurately describe the flavor: “If we had time for everybody to say what their descriptors were, you would find that there would not be the same consensus. … I may taste something and call it green pepper and you may taste exactly that same thing and call it pea pods. And that’s because in your experience, that’s what you think of pea pods and this is what I think of green peppers. It’s a language thing. It’s not an oil thing.”

I plow on through and finally get to the last page of the evaluation. Here is where tasters rate the oil in terms of astringency (that mouth drying sensation I most often associate with black tea and tannic red wine) and robustness. There are also boxes to check if the oil is deemed “defective.” Defective seemed like a scary box, and since I really couldn’t pick out defects anyway, I skipped it. My reward for finishing is a couple bites of apple and some swigs of water to rinse away as much residual taste from the oil as possible.

Once everyone finishes evaluating the first oil, the tasters remove their blinders to discuss the results. Everyone, apprentices and full-fledged tasters alike, share their “numbers:” their results for defects, positive attributes, and astringency/robustness ratings. Ash reports the average scores for each page, and we discuss any lingering issues with the oil. Then we go to the oil table and pick out the second sample and repeat, twelve more times.

Most of the oils pass without much of a hitch. Even if a couple of tasters find a defect in an oil, the oil gets a green light. There must be majority consensus on a defect in order to flag the oil as problematic. But a couple of oils seemed problematic, and one was even held as a re-test. “Those oils concern me because if so many trained palates think that there’s something not right, there’s probably something not right, even if we’re not all calling it the same thing. And I hate to see those get passed as extra virgin just because there’s no consensus,” said Ash.

Given all of this discussion it comes as little surprise that the tasting goes on for over two hours. The first six or so oils taste distinctive, but after we passed the half-way mark, my palate began to suffer and my scores started to diverge markedly from the panelists. By the last oil, the most pungent of the bunch, I had a stomachache and my mouth was dry. I was also strangely hungry for someone who had probably swallowed half a cup of oil over the course of the morning.

Both Darragh and Ash commiserated with my discomfort. “Everyone has developed an ‘after’ routine,” said Ash. We all split and [run] to different places to have lunch. I always have lunch in the same place every time: Betty’s. … I always need a big bready thing after I do a tasting.”

Darragh had an even stronger suggestion: “Go get a cheeseburger.”

Now your turn

If you want to learn more about California Olive Oil and sensory analysis, the COOC will be offering classes once a month on Monday evenings starting in September. Classes will include lessons on tasting, food pairings, and cooking. Online registration will begin on the organization’s website in July. Cost for the class is still being determined, but Darragh maintains that it will be “really inexpensive.” Visit the California Olive Oil Council online for information.

Kate Williams was raised in Atlanta with an eager appetite. She spent two years as a test cook at America’s Test Kitchen before moving out to Berkeley to write, eat, and escape the winter. She currently writes for Serious Eats and The Oxford American, in addition to her work at Berkeleyside NOSH.

Author: ‘You may not like what’s lurking in your olive oil [12.08.11]

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Kate Williams has been writing about food since 2009. After spending two years developing recipes for cookbooks at America’s Test Kitchen, she moved to Berkeley and began work as a freelance writer and...