This is NancyHarmon Jenkins’s seventh cookbook. (Houghton Mifflin Harcourt)

The book explains how to taste olive oils and how to describe them. (Joseph Victor Stefanchik/For The Washington Post)

American consumers spend hundreds of millions of dollars each year on extra-virgin olive oil alone, and we’re generally on the same page about the notion that it’s a healthful fat. Yet we know less about it, and about olive oil in general, than we should. Only one in four of us is aware that the oil does not improve with age, and 85 percent of us think “light olive oil” has fewer calories than other olive oils, according to a recent study. (For the record, the designation refers to refined olive oil with little aroma or flavor.)

The research results are reason enough for Nancy Harmon Jenkins to have written “Virgin Territory: Exploring the World of Olive Oil” (Houghton Mifflin Harcourt, February 2015, $29.99). More significantly, the respected author and historian is passionate about the subject, and clearly fascinated by it. She has spent four decades cooking, learning, sampling, touring, harvesting her own olives and trying to vanquish misperceptions about the oil. (Yes, Virginia, you can fry in extra-virgin olive oil.)

This is her seventh cookbook, with much more to offer than her well-written, mostly Mediterranean-based recipes. There are the expected Great Moments in olive oil history, because Jenkins is recognized as an expert in the field and likes to share information. The chapters on the process of making oil and the science around the ingredient are in layman’s terms.

Her explanation of why we should care about identifying what is truly “extra-virgin” is presented without hyperbole. Such oil is extracted and processed without chemical treatment and refining; it contains no more than 0.8 grams of oleic acid per 100 grams of oil, and it must be free of defective flavors and aromas. It does not necessarily come from a first pressing. Its combination of polyphenols is said to be the most healthful of all olive oils’.

Jenkins’s bottom line: Rely on taste more than labels.

To that end, she walks us through how to taste olive oils and the language with which to describe them, preferably at a venue where you can sample more than one or two at a time. Beyond calling for extra-virgin­ olive oil in a preface to the recipes — a matter of style that might not get picked up by less-careful readers — Jenkins does not specify particular types of olive oils for certain dishes. But she does list reliable sources and brands, including Costco’s Kirkland Signature Extra-Virgin­ Olive Oil and Trader Joe’s Kalamata Extra-Virgin Olive Oil from Greece.

One oil for cooking and one for finishing are all that’s needed in a discerning home cook’s kitchen. Proper storage is more crucial, she says, meaning keep it out of the refrigerator and away from the heat of a nearby stove or microwave.

Recipes:


(Deb Lindsey/For The Washington Post)

Soupy Spanish Rice With Clams


(Deb Lindsey/For The Washington Post)

Chilies-Stuffed Steak


(Deb Lindsey/For The Washington Post)

Anchovy Salad Dressing


(Deb Lindsey/For The Washington Post)

Gluten-Free Olive Oil Muffins


(Deb Lindsey/For The Washington Post)

Becchina’s Oven-Roasted Fish