The difference between extra virgin olive oil and olive oil

I vividly remembered the moment olive oil entered my life. It was 1974 and I was on one of those "200 countries in three days"-type trips with other students from my high school. Our first stop was Madrid. I was way too keyed up to rest through the jet lag, so I started walking around the city. Everywhere I went, I could smell this incredible aroma — and I couldn't for the life of me identify it. I asked everyone who spoke even a little English what the smell was, and no one seemed to understand what scent I was referring to. That night at dinner, I found my answer: potatoes, fried in olive oil.

I had never even heard of olive oil. To me, olives were those tasteless black things from a can. I would soon learn that the reason no one could identify my phantom aroma was because what I smelled was so ubiquitous in Madrid that I was the only one who even noticed. But the flavor of those potatoes was astonishing, and my olive oil obsession began that day. (It shows absolutely no sign of abating, either.)

In the years since my personal olive oil epiphany, the U.S. has become obsessed with olive oil, both for its incredible flavor and for its remarkable health benefits. While you can typically find numerous olive oils on supermarket shelves, different bottles are better for different applications in the kitchen. Here's what you need to know.

First, What Exactly Is Olive Oil?

Olive oil is a liquid fat, extracted by pressing, or grinding and then pressing, the fruit of the olive tree. The tree, Olea Europaea, is a member of the family Oleaceae, originating in the Mediterranean Basin. The world's supply of olives, and therefore olive oil, comes primarily from Spain, Italy, Greece, Turkey, and catching up, the US. Olive oil is used in cooking food, in soaps, in cosmetics, pharmaceuticals, as lighting, and — still to this day — in a number of religious ceremonies.

The oldest method for obtaining the oil (and the way many believe remains the best) involves crushing the olives between two large stones, and then pressing the pulp to extract the oil. The less heat generated in processing, the better. The method and care with which the oil is pressed, along with whether or not it's refined and blended, all contribute to the "grade" and price of the oil.

Extra-Virgin Olive Oil

The distinction "extra-virgin" refers to the first pressing of the olives. Essentially, it's the cold-pressed oil yielded from just a pressing of whole olives, no additional heat or chemical treatment applied; thus, EVOO is considered an unrefined oil. During the extraction process, great care is taken to keep the temperature of the grinding and pressing as low as possible in order to retain all of the purest flavors and health benefits of the oil. The result of the meticulous processing standards is that this category of olive oil contains the lowest percentage of "free acidity" (or oleic acid) amongst all grades: less than 0.8%.

In practical terms, that means that this is the oil you want to use in a salad, or as a finishing drizzle over a dish after cooking. Extra-virgin olive oil is by far the most expensive variety, but it also offers the most sapid flavor.

Can I Cook With Extra-Virgin Olive Oil?

Now here's where I will part ways from the advice of many chefs when it comes to this variety of olive oil: As long as the temperature of my cooking heat stays below the range of 350-415 degrees F, I will definitely cook with good extra-virgin oil. It's true that at temperatures above that range, the flavor of the oil begins to rapidly deteriorate and an acrid burned taste predominates. But if you are mindful about monitoring your heat, cooking with extra-virgin olive oil adds incomparable flavor to whatever you're cooking.

Do I suggest you cook with a really expensive extra-virgin olive oil? I do not. But you can definitely find good-quality EVOO for everyday cooking. (California Olive Ranch brand is one such example that's available at most major grocery stores.)

California Olive Ranch Medium Extra Virgin Olive Oil (16.9 fl oz)

Virgin Olive Oil

Virgin olive oil ( which is not as ubiquitous on U.S. supermarket shelves as other types) is next down on the list. While it is also considered an unrefined oil, it contains up to 2% free acidity. This oil is less expensive, but can be (almost) as good as extra-virgin. The flavor that virgin olive oil offers is still rich in untarnished olive essence, but it is less intense compared to EVOO. That said, if you find one that has a taste you love, it can be used in salads, as a finishing drizzle, and in lower heat cooking, just like extra-virgin olive oil.

Pure and "Light" Olive Oil

This category of oils is far more processed, with less care in the pressing, compared to virgin and extra-virgin. Usually, these olive oils consist of virgin olive oil blended with refined (meaning, the oil was extracted using chemical and/or heat treatments) olive oil.

Though these are the bottles currently in many home cooks' pantries, the olive flavor is barely existent in these lower-shelf categories. These are oils simply for cooking, not for salads or drizzling; you can even use them to deep-fry. For these reasons, in my opinion, you might just as well move to the less-expensive vegetable or corn oil.

Also be aware that "light" olive oil is NOT any lower in fat or calories compared to other olive oils. Light is simply a marketing term that refers to the fact that the oil is usually lighter in color and always lighter in olive flavor than other olive oils.

• Be sure to explore our entire collection of Olive Oil Recipes.

The world of olive oils remains ever-fascinating to me. I genuinely relish my small bottle of great extra-virgin, reserved for special salads and as a finishing oil. However, one thing to keep in mind when shopping for olive oil is that while you may be willing to invest in a high-quality oil, good olive oil is, in fact, perishable. I mention this only to say that although it can be tempting to "stock-up" and buy the 3-liter bottle, if your household doesn't tend to go through olive oil rapidly… reconsider.

Always store your olive oils away from direct heat and light — such as in a cabinet that's not near your stove/oven. If your oil doesn't come in a dark bottle, I'd urge you to procure one and transfer the oil into it. I once came across a (not great) white wine that came in a black bottle; my husband and I survived the wine, and the bottle is now my official EVOO container.

Related:

• What to Look for When Buying Olive Oil
• 25 Ways to Bake With Olive Oil Instead of Butter
• 6 Smart Ways to Use Olive Oil