Every cook knows olive oil is essential. For Tom Mueller, it’s the lifeblood of Western Civilization. In Extra Virginity, his lively, earnest, exhaustive, and sometime exhausting debut, Mueller discovers oil not only as food, but as fuel, lubricant, medicine, skin care, perfume, aphrodisiac, religious symbol, and way of life. In the words of one aficionado, true extra virgin olive oil is the stuff that “makes you get down on your knees and say, ‘Fuck’.”

As Extra Virginity explains, all olive oils are not equal. Each country has its own varieties, such as biancolilla, cornicabra, and racioppella in Italy, picual and arbequina in Spain, and koroneiki in Greece. Oil tasters talk like sommeliers; to them, oil can have pleasant notes of cucumber and artichoke or taste like pipi de gatto (cat pee). More broadly, oils range in quality from lampante (lamp oil) to extra virgin, a term coined in 1960 by the European Parliament. Unfortunately, as Mueller reports in the book’s central exposé, rampant fraud and lax regulation have made “extra virgin” meaningless. If you buy a bottle labeled extra virgin, there’s a good chance it’s lower quality or adulterated oil that pretends to be the real deal.

With its tight and obsessive focus on an ostensibly mundane topic, Extra Virginity follows in the spirit of Mark Kurlanksy’s Salt and Michael Pollan’s The Botany of Desire. Mueller deftly alternates between reportage from the groves, factories, laboratories, kitchens, and tables of Italy, Greece, Spain, Australia, Israel, and California and historical background, which includes the following tidbits:

• Jesus’s foreskin and umbilical cord were supposedly preserved in olive oil in 11th century Rome.
• A Cretan proverb says, more or less, “Eat olive oil to come at night, eat butter to sleep tight.”
• Thomas Jefferson, impressed by olive trees in Europe, started an olive plantation in South Carolina and insisted on an olive branch in the eagle’s talon on the Great Seal of the United States.
• In World War II, Italian partisans hid from Nazis and Fascists inside the hollow trunks of olive trees.
• Don Corleone, of The Godfather, was based on a olive oil baron and mafioso Joseph Profaci.

Extra Virginity begins at an elite olive oil tasting session in Milan, an event Mueller mocks until he partakes and begins to appreciate its subtleties. As the book unfolds, he becomes hooked on the green Kool-Aid, as in this account of a three-day olive oil conference in Verona:

The audience tasted the oils on their own, after which the chefs explained how to blend them into the foods, pointing out how oil brought out hidden flavors in the dishes, and how each oil, with its own distinct pungency, fruitiness, aromatics, and mouthfeel, changed the fundamental character of the food in different ways, highlighting the succulent flakiness of the mullet and the floral notes hidden in the chickpea soup, and causing the mousse’s sweetness to linger luxuriously on the tongue.

Beyond such gourmet breathlessness, Extra Virginity joins a growing number of books about how food is produced, regulated, labeled, and sold. The book is less gloomy than Four Fish, Paul Greenberg’s apocalyptic appraisal of the seafood industry, less morally outraged than Eating Animals, Jonathan Safran Foer’s polemic against the meat and poultry industry, and less dogmatic than anything by Michael Pollan. Still, these books share a message: the food we eat has moral, economic, political, environmental, and health consequences. Ultimately, Mueller emerges as a champion of the underdog: whether it’s the small oil maker in Italy, Spain, Australia, or California or the consumer without knowledge or access to “the queen of fats.”

Keith Meatto is co-editor of Frontier Psychiatrist. His recent reviews include Adam and Evelyn, Sex on the Moon and Between Parentheses. For more reading recommendations, see his Top 10 Fiction Books of 2011 and Top 10 Nonfiction Books of 2011.