In the August 13, 2007, issue of the magazine, Tom Mueller wrote about corruption in the olive-oil trade. By the late nineteen-nineties, olive oil—often cut with cheaper oils, such as hazelnut and sunflower seed—was the most adulterated agricultural product in the European Union. The E.U.’s anti-fraud office established an olive-oil task force, “yet fraud remains a major international problem,” Mueller wrote. “Olive oil is far more valuable than most other vegetable oils, but it is costly and time-consuming to produce—and surprisingly easy to doctor.”
Nearly five years later, fraud remains a problem. Mueller has expanded the scope of his article’s research with his recent book “Extra Virginity: The Sublime and Scandalous World of Olive Oil,” which focusses on the contamination of olive oil not only by seed oils but by the misuse of the label “extra virgin” on olive oils that don’t meet that designation’s standards. Mueller recently took the time to answer questions on olive oil and the risks involved in its trade; an edited version of the exchange appears at newyorker.com.