Bottles of olive oil at a factory in Dos Hermanas, SpainMarcelo del Pozo / Reuters

Olive oil is not what you think it is. According to Tom Mueller, the author of Extra Virginity: The Sublime and Scandalous World of Olive Oil, an olive is a stone fruit like a plum or cherry—meaning that the green-gold liquid we extract from it “is, quite literally, fruit juice.” And, while we’re blowing your minds, have you ever stopped to wonder what “extra virgin” means? “It’s like extra dead or semi-pregnant,” Mueller said. “I mean, it doesn’t make any sense at all.” This episode we visit two groves—one in the Old World, one in the New—to get to the bottom of olive oil’s many mysteries. Listen in this episode as we find out why the ancient Romans rubbed it all over their bodies, and whether the olive oil on our kitchen counters really is what it says on the label.

Olive oil’s original home lies along the shores of the Mediterranean, where its wild ancestor, the oleaster, can still be found today. Somehow, people realized that the bitter berry from these hardy trees tasted excellent when brined in salt and, even better, could be crushed to produce a liquid fat that was not only delicious but, Mueller says, burns as hot as benzene and has twice the heat-energy content of carbon. By the seventh century BCE, olive-oil production was taking place at industrial scale: Olive presses excavated at Ekron, in modern-day Israel, were capable of producing 500,000 liters of oil a year. The demand was equally enormous: Olive oil powered lamps and preserved and enhanced food, and it was used as an all-purpose medicine, a contraceptive—even an aphrodisiac. Olive oil was so critical to Greek and Roman culture that wars were fought over it and fortunes made, much like the petroleum sheikhs of today.

Today, olive oil is more popular in the kitchen than in a lamp, but it still enjoys a superior status to its fellow fats—particularly since the 1980s, when it began to be promoted by medical researchers as a key component of the heart-healthy Mediterranean diet. But all is not well in the olive groves. In Italy, millions of olives have already been killed by Xylella fastidiosa, an insect-borne pathogen that was detected in 2013. The disease can cause mature trees to die of thirst within two years. We speak to Rodrigo Almeida, a professor of environmental science at the University of California, Berkeley, to find out how worried we should be about the future of Italian olive oil. Meanwhile, olive-oil fraud is rampant in general, but especially in the United States, as profits from fraudulent oil can be more lucrative than dealing cocaine.

But fear not: We won’t leave you on this depressing note. Instead, olive-oil growers Anna Casadei of the Castello del Trebbio in Tuscany, and Kathryn Tomajan and Robin Sloan of Fat Gold in Sunol, California, lead us through harvesting, milling, and, most importantly, tasting, in order to equip us to buy, use, and love olive oil nearly as much as they do. Listen in now, and then enjoy a big glug of oil over your veggies—heck, we won’t judge if you want to rub it on your skin, too!


This post appears courtesy of Gastropod.

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