Have you ever tasted a tomato leaf?
As a bona fide black thumb who’s never taken to backyard gardening or the great outdoors, I sure haven’t. But ‘tomato leaf’ is a big tasting note in the olive oil industry, apparently, and at Cobram Estate’s reception lounge in Woodland, California, technical director and chief olive-oil maker Leandro Ravetti tells me it’s a common characteristic of oil made from picual olives. A minute before, I’d swigged a dram of chartreuse oil from a plastic pill cup, and sure enough, it tastes vividly of ripe tomato flesh warm from late-summer sunlight. There’s also a touch of bitter and bracing, as if I’d just mainlined a pile of fresh basil leaves. No—not basil, the taste is meatier, muskier in that compelling tomatoey way, but also inescapably verdant. It’s a breezy October morning and all I can think about is my sudden roaring hunger for raw tomatoes on toast.
Huh. I guess that’s what tomato leaves taste like.
Olive oil is one of those foods we embrace on faith. Science says it’s good for you, chefs say the quality stuff makes other foods come alive, and pretty green bottles of it can hit $40 on store shelves. We accept the idea of ‘good’ olive oil the way we accept the idea of ‘grassy’ flavors, despite never munching on blades of grass. But what is good olive oil? What makes it good, what should it taste like, and how do you shop for it if you can’t taste it beforehand?
These are the questions I came to California to figure out. Little did I realize the answers have as much to do with the weird world of food supply chains as they do with growing olives.
When Good Olive Oil Goes Bad
Most people can tell you how to spot a good tomato, but the traits of good olive oil, a food many of us eat every day, are surprisingly opaque. Take Colavita, which is Amazon’s best-selling extra-virgin, and at 29 cents an ounce you could call it the Two Buck Chuck of cooking fats. If you shop at a major American supermarket, you’re likely buying a commodity extra-virgin like Colavita. That doesn’t mean it’s bad, per se, but you should know what you’re paying for.
To vastly over-generalize the byzantine global olive oil trade, large commodity olive oil companies buy oils from all over, then blend them into a consistent product. The brokers and aggregators they buy from are in turn buying smaller lots of oils from regional producers, which are in turn buying harvests of olives from dozens to hundreds of small farms. A three-liter tin of commodity extra-virgin could conceivably contain oils from thousands of orchards, which is pretty cool when you think about it, but consider that for every one of those sources, there’s that many more ways for the processing to have gone wrong, or for the oil to have been mishandled. Assuming, of course, that it’s actually pure olive oil sitting in there, and not, say, adulterated with half a dozen refined fats.
Amazon says that bottle of Colavita is "imported from Italy," which is a clever way of saying the bottle itself was shipped from Italy without guaranteeing the provenance of the oil inside. If you squint at the back label though, you’ll see a fine print disclaimer: "Contains oil from one or more of these countries," with a legend you can use to decode the country codes printed on the bottle itself.
By olive oil standards, this is actually pretty responsible labeling! Other brands aren’t as above-board. The famously fraudulent global olive oil industry has little interest in arming consumers with actionable information about their product. Agents along a complex supply chain often blend Italian oils with olive oil from other countries and sell it as pure Italian. Companies stretch good batches of extra-virgin with tasteless soybean or safflower oils, or blend in oil made from older olives that’s refined just enough to make it palatable. A 2014 congressional report on adulterated foods, including olive oil, details these scams.
Fraud aside, even 100% pure extra-virgin olive oil will deteriorate in the bottle, and if it’s stored improperly or sits on a supermarket shelf for a year or two, it could taste rancid before you break the seal. Regulations exist to combat these practices, but they’re rarely enforced. After all, olive oil is a commodity governed by the iron laws of capital; for much of the industry, yield and profit matter far more than quality.
How to Recognize Good Olive Oil
Then there’s the minority: small-batch boutique olive oils made by skilled producers around the world, either directly from their own olive orchard or from nearby sources. If Colavita is the Two-Buck Chuck of olive oil, these specialty brands are the natural wines and grower Champagnes. They’re intense and complex. They taste vividly of olives and give you a sense of place. They are, theoretically, good olive oils. You can expect to pay $1.50 to $3 an ounce for these, a price that reflects not just ostensibly higher quality olives, but the higher cost of labor, manufacturing, and distribution that accompanies artisan food production. Of course, there’s no guarantee that a $40 bottle of olive oil will actually be good, or if it is, that you’ll like its particular character. Like any specialty food, the relationship between price and value gets tricky on the high end of olive oil.
So what if you just want reliably good olive oil—less expensive than the boutique stuff, but still responsibly made, fresh, and delicious enough to make you smile? You know, like a good table wine, a bottle in the $15 to $20 range that has a lot going on but won’t break the bank. Brands like Manfredi Barbera & Figli's Frantoia, California Olive Ranch, and Cobram—where I visited—excel in this category. These are companies that sell olive oil in the vicinity of 75 cents an ounce, about triple the price of that Colavita, but half the price of a super-premium bottle.
Just like in wine, a lot of California companies are making good olive oil these days. California Olive Ranch is the biggest, but since launching in the US in 2014, Cobram Estate is one of the fastest growing brands in the category. It’s actually an offshoot of an Australian company called Boundary Bend, founded by agriculture school buddies Rob McGavin and Paul Riordan in 1998, that’s captured 30% of the Australian olive oil market. In addition to loving flat whites and having funny accents, Australians are big fans of olive oil; the average Australian consumes 1 3/4 liters per person per year, compared to just under a liter per person in the US. (Greeks, Italians, and Spaniards consume about 10 times that American figure, just so you know.) Boundary Bend’s success in Australia has translated to winning dozens of international olive oil competitions and a $360 million valuation.
So when Cobram’s PR team offered to fly me out to see their Central Valley orchard and factory firsthand, I was intrigued. I’m skeptical of press junkets, but the Cobram people pride themselves on transparency, from their on-site lab that reports findings to the California Olive Council to more than a dozen peer-reviewed industry papers on olive oil science. Besides, I’ve liked their olive oil for years. The first time I tried some, as an editor at a magazine that received free food samples several times a day, I swiftly palmed the half-liter office bottle to hoard in my home kitchen. It lasted about a week.
In a stark departure from the big commodity brands, Cobram Estate is completely vertically integrated: the company grows olives (directly or through contracts), picks them, mills them into oil, then bottles and ships them, all on-site. Most of California’s olive oil companies work the same way, but thanks to Boundary Bend’s vast coffers, Cobram has been able to expand aggressively, scale up production, and invest in pricey equipment. The idea, McGavin says, is to couple stringent boutique standards with a massive supply of raw material, using advanced technology and industrial scale to raise the standards of oil-making while keeping competitive with larger commodity brands. Here, then, was a chance to see what ‘good’ olive oil means at both ends of the manufacturing spectrum, and how they might meet in the middle.
How Olive Oil Is Made
A mechanical olive harvester looks like a car wash on wheels. As the 14-foot-tall leviathan rolls through the orchard, it swallows olive trees whole while rotary bristles inside the arch whack olives off their branches. While the harvester trundles down the row, a truck drives in tandem one row down, and a conveyer belt on the harvester reaches over the trees to deposit fistfulls of olives into the truck’s hopper.
The olives that Cobram is harvesting the morning of my visit are a mix of green, purple, and black; while color is an indicator of olive ripeness, Ravetti’s team relies more on the olives’ oil accumulation, flowering times, moisture levels, and other environmental factors. In July, the team starts testing olives, lot by lot, to determine the order in which they’ll be picked. Then they work out an action plan with president of US business, Adam Englehardt, to match that picking order with the factory’s capacity. California olive season runs a tight eight weeks in October and November, and once it starts, picking, processing, and milling becomes a 24/7 operation. Cobram’s factory sits in the middle of their 475-acre orchard with 10 different olive varieties planted, though as most of those trees are too immature to bear fruit, 90% of the company’s olives right now come from nearby growers that in many cases have exclusive contracts with Cobram.
With an orchard that size, scheduling picking and milling becomes a massive challenge of logistics and engineering, Englehardt explains. That’s because every olive is milled the same day it’s picked, usually within just a few hours, so it can be blended into larger batches for a consistently fresh product. Olives left off the tree too long undergo an enzymatic process called hydrolysis, where triglycerides (fat molecules) in the presence of water break down into diglycerides and free fatty acids. Meanwhile, oxidation breaks down chemical bonds in fatty acids, releasing peroxides that further break down into other compounds that cause rancidity in oil. Eventually the olives ferment, and after that, rot, and every stage of this degradation introduces off flavors to the finished oil. This happens a lot in regions where small commodity olive growers have to wait for space in a nearby crushing facility to become available. If the facility is backed up enough, the olives turn before they can get crushed, and the resulting oil will have to be heat- and chemically-refined in order to be edible. So once the olive is off the tree, the clock is ticking.
Cold-pressed olive oil is just that: olives crushed and ground into an oily juice, solely with mechanical pressure. About 20% of an olive’s fresh weight is oil, McGavin explains, but the oil itself is essentially flavorless. You have to rupture an olive’s oil sacs so the fats can marinate with the fruit’s flavorful skin, flesh, and seed. Cobram grinds the olives into a paste for about 45 minutes using a traditional hammer mill, which works on the same basic principle as those giant car crushers, then runs the paste through a 3,000 RPM centrifuge to separate out the now olive-infused oil.
But the clock ticks on. For one, the newly freed oil needs to rest so any residual water and solids can separate out. But even once you’ve removed any hydrolysis-inducing moisture, fresh oil in the presence of air will keep oxidizing. So after Ravetti’s team takes initial readings of the fresh oil and tastes it to see which batches to blend it with, it gets piped into steel tanks for cold storage, which are flushed with nitrogen to halt further air exposure. Sitting in these tanks, sequestered from heat, light, and oxygen, is as close to cryogenic storage as olive oil gets. But even under optimal conditions, the oil is deteriorating: you can’t halt oxidation completely, and enzymatic activity that began the minute the olive was crushed continues on, though at a slower pace. As we talk through the forest of tanks, Englehardt says that they aim to keep oil in this condition for no more than a year.
We move on to a smaller room with some crates on wooden pallets. Englehardt explains that these are boxes of bottled oil, ready to be shipped. “Is this it?” I ask, surprised by the meager size compared to the giant tanks we just left behind. He nods. Even the minimally air-exposed act of transferring olive oil to nitrogen-flushed bottles accelerates the oil’s deterioration. “We try to keep only four weeks’ worth of inventory in these bottles,” he says. The rest is sitting in cold storage as oil or still on the tree as whole olives.
Decoding the Grade: The Difference Between Extra-Virgin and Virgin Olive Oil
Extra-virgin olive oil is generally defined as 100% cold pressed olive oil with a maximum of .8% acidity and no sensory defects. Virgin olive oil, the next grade down, allows up to 2.5% acidity with minor defects. Beneath these two tiers lie an assortment of lower quality grades that all require heat and/or chemical refinement to taste palatable; these make up the bulk of the commodity olive oil market.
You can measure acidity—and a whole host of other related critical factors, such as peroxide counts and signs of pests or disease—in a lab, but sensory defects come down to a tasting panel of experts trained to look for flaws like rancidity, barnyard or alcohol flavors, and ‘fustiness,’ a sign of fermentation. Nancy Ash is one of those experts. In addition to working as an olive oil consultant for more than 20 years, she’s also a tasting panel member at the California Olive Oil Council, a regional trade organization dedicated to raising standards for the California oil business and communicating those standards to the public.
“An olive oil that shows no flavor defects and passes chemical analyses such as acidity tests can be called extra-virgin,” she says, “but a passing grade just means you didn’t fail. It could be a D; would you be happy with a D?” An oil that lacks manufacturing defects could still taste bland, unbalanced, or just plain unenjoyable, yet it can earn the same grade as an award-winning bottle. That may be for the best, since the alternative, maybe something like a Robert Parker-esque point-based scoring system, is probably more cumbersome and subjective than it’s worth. The bigger issue, Ash goes on, is that since olive oils deteriorate over time, the grades they receive from a tasting panel aren’t necessarily reflective of what you get when you open a bottle.
“Even the best extra-virgin olive oils are going to taste rancid three years later.” For regular cooks in search of great olive oil, this is the most important thing to keep in mind. If you buy or receive some fabulous bottle of extra-virgin olive oil, don’t save it for special occasions in the back of the cupboard. Use it now, while it’s fresh and punchy and delicious. It’s not a collectible.
So what, then, is a regular American cook to do? Ash’s biggest piece of advice is to seek out oils with best-by dates as far ahead into the future as you can find. Very small specialty producers may put harvest dates on their bottles, but larger companies working with multiple lots and orchards, as well as the commodity giants, mostly go by bottling dates. In the EU, a best by date is typically 18 months after the bottling date, while in the US it’s closer to two or three years. A far-in-the-future best by date doesn’t guarantee an oil has been handled well along the supply chain, but it at least increases the likelihood that the oil in the bottle isn’t too old. Dark bottles are more resistant to heat and light deterioration than clear, and even though small bottles might cost more per ounce than three-liter tins, they’re generally preferable; once you open the bottle and expose the oil to air again it’ll begin to degrade even faster, and unless you’re cooking restaurant-sized batches of food on the regular, you probably won’t finish a hefty tin of olive oil before those flaws become noticeable.
Ash goes on to explain how California producers are getting more technical on labels to build demand for higher quality oils. The California Olive Oil Council has launched a pilot program of an endorsement seal for certain brands. Some producers are putting harvest dates on their labels, and others are listing polyphenol counts, which range from 150-200 on the lower end up to 600 or so. Higher polyphenol counts generally correlate to oils that last longer, Ash says, but that’s not a guarantee, and some may find the bitter, pungent taste that comes with super-high counts to be unpalatable. Cobram’s Australian division prints antioxidant data on each bottle, and McGavin says that once the US team gets enough data, they’ll replicate the practice here, possibly even this year.
For Cobram, coming to America was about more than venturing into a new market. With orchards in opposite hemispheres, the company enjoys the nifty advantage of two separate growing seasons roughly six months apart, which translates to fresher olive oil year-round.
Which has me thinking, finding a bottle of good olive oil is a lot like buying a tomato after all. Buy from reliable purveyors, seek out what looks fresh, don’t rely on fancy names and labels, and trust your instincts. After all of one day in a field and a few months spent thinking about olive oil, I don’t feel qualified to say what good olive oil really means. But I know it involves a lot more than the words ‘extra-virgin.’
Ready to Splurge? Where to Buy Great Extra-Virgin Olive Oil
When it comes to oils that she keeps in her pantry, Ash admits she’s a biased source—many of her favorites are made by friends, clients, or both. But she says she happily "blind buys," that is, orders without tasting the new batch to make sure she’ll like it, from Katz Farm, the Sicilian-leaning Bondolio, Grumpy Goats, and Frantoio Grove. I was also curious about great olive oils made in Europe, so I reached out to Nick Anderer, the founding chef of New York’s Marta, Martina, and Maialino, a trio of Italian restaurants from Danny Meyer that specialize, unsurprisingly, in high-end regional Italian specialty foods. Every fall, he and his team place advance orders for the first pressings of the following year’s olives from a small list of Italian producers he’s come to trust year after year.
“I’m looking for oil that’s alive,” he says. “I want vibrancy; I should cough if I’m tasting it raw, and I want peppery and grassy notes that feel very present.” Beyond that general principle of robust intensity of flavor, Anderer prefers different producers’ oils to finish different types of food. “For red meat dishes, I want more of a gut punch of bitterness,” he says, so he reaches for a high-polyphenol Tuscan oil by Laudemio. But an oil that strong would be overkill on, say, delicate fish or vanilla ice cream. His “rounder, almost drinkable” oil of choice for those foods is an unfiltered bottle from Capezzana, a deep-green oil that’s “super rich on the tongue,” ideal for a simple pasta like aglio e olio. He’s also a fan of Olio Verde, a Sicilian oil made exclusively from Castelvetrano olives, as its brininess works wonders with seafood. And for special occasions, he breaks out his bottle of Manni, a super-premium bitter Tuscan oil that mostly sees action in the fine dining restaurant market.
If you’re just starting to explore the world of high end olive oil, go try something similar. Hit up your favorite Italian restaurant—or Spanish, or Greek, or New American, or Lebanese—and ask what olive oil they keep in the kitchen. Then splurge on a few bottles, buy some pita or baguette, and get to tasting as much as you can. After all, they say olive oil is good for you.
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