Idiot’s Guide: Olive Oil
For the coastal cultures of the Mediterranean, the oily flesh of the olive was the stuff of life itself; a source of valuable and energy-dense fat which was stable, flavorful, and portable. To the emporia of Ancient Greece, amphorae of olive oil were as valuable a commodity as petroleum is today.
The way people talk about olive oil these days, you’d hardly know circumstances had changed, yet arguably the olive oil craze is a recent development; a product of the popular nutrition movement. In many cases, though, we do ourselves a disservice by just treating olive oil as “health food” rather than the incredibly versatile ingredient it is. Olive oil is the ultimate edible oil – comparable in utilization to that other favorite fat, butter. Depending on the process used to produce it, olive oil can be deeply and uniquely flavorful or mellow and mild, a perfect alternative to other popular vegetable oils.
So I ask you, how much do you really know about olive oil? Hopefully by the end of this article, you’ll know more than enough to make it a regular part of your diet.
The first thing to know about olive oil is how it’s made. As far back as 2500 years ago, the olive was being crushed for oil, and fundamentally, the process hasn’t changed much. Olive oil is one of the few vegetable oils (nut, avocado, and coconut oil are other notable ones) that doesn’t require modern industrial production processes to extract.
There are two methods generally used to produce olive oil – so called “cold” and “hot” pressing. The difference is really one of temperature; cold-pressing must be done below 25 degrees Celsius (around 77 degrees Fahrenheit) and is seen as the superior technique for retaining the distinct olive flavor, while hot-pressing tends to be associated with industrial-scale production of more neutrally-flavored oils as it has a tendency to reduce the quality of the product.
Alongside olive oil, the modern olive oil industry also produces “pomace oil”, which is extracted by treating the olive paste with chemicals to encourage further oil production. Legally speaking, this oil cannot be considered olive oil, but when purchasing oil a consumer should make sure they’re getting the real thing – a lot of cheaper olive oils are adulterated with pomace.
Other potential tripping-points on the label might be the so-called “grades” of olive oil. These grades are tied to the production process and are very important to consider when purchasing oils, as the grades differ greatly in flavor, texture, and price. Here are the most common grades:
Extra Virgin (EVOO): Extra-virgin olive oil has become probably the most famous of the olive oil grades, but many chefs, even professionals, use it incorrectly. Extra-virgin oil is the highest-quality, most flavorsome grade, suitable for consumption on its own (drizzled over bread or mixed into salad dressing, for example. It can also be used for quick sautéing and low-heat cooking, but beware! Despite what you’ve learned from Rachael Ray, you should stay away from it when going into high heat (like frying) beyond 400F or cooking for long periods, as it tends to impart off-flavors and may potentially form dangerous compounds if overheated.
Virgin: The ‘virginity’ of olive oil refers to the process used to produce it; virgin oils are produced by crushing only and are not treated with chemicals. If your oil is blurry, it means that your oil has not been strained; this is generally seen as a mark of quality but it may reduce the oil’s quality for higher-heat cooking. Like extra-virgin oil, you should probably avoid high-heat cooking, though virgin oil can be excellent oil for Mediterranean stews and dressings, as well as an admirable replacement for EVOO if you don’t want to shell out for the good stuff.
Refined Oil: Often marketed as “pure” or simply as olive oil, refined oils are products of industrial processing techniques, which includes using chemicals. These oils can be good substitutes for other oils, particularly canola, as their treatment process tends to neutralize the distinct olive flavor – it may also mellow or even eliminate the distinct green color of a good olive oil. They are also considerably cheaper than other grades of oil. That being said, they are not much better than virgin oils in terms of heat tolerance. If you’re looking to get olive oil into your diet, this may be the cheapest and most universal option.
Light Oil: Filtered to remove the potentially flammable or off-tasting particulates, light oil is the perfect oil for someone who wants to use olive oil in high-heat cooking. Lightness is independent of the level of virginity or refinement, so if you’re insistent on channeling your inner Rachael Ray, go with light extra-virgin olive oil for the least chance of off flavors.
To conclude, let’s talk a little about health. Calorically speaking, olive oil is no different from any other oil – containing roughly 120 calories per tablespoon. The health benefits of olive oil are associated with the way the calories are distributed. A tablespoon of olive oil contains an impressive 11g of unsaturated fat (10g monounsaturated, 1.5g polyunsaturated) and 2g of saturated fat, compared to butter’s 7g of saturated fat and 3g of monounsaturated. Unsaturated fats are associated with lower cholesterol. Olive oil is also full of antioxidants called polyphenols which are associated with improved mental and bone health. Beyond culinary applications, olive oil is also famously popular in cosmetics – the Greeks and Romans used it like soap, while modern oleuphiles praise its moisturizing properties.
In the culinary world, olive oil has a wide variety of uses. Extra-virgin oils are great in dressings and dips like pesto, tzatziki, chimichurri, and tapenade. It’s also a fantastic option for making mayonnaise, imparting a vegetal flavor that’s perfect for Mediterranean mayo applications like aioli. Italy has also produced some decidedly sweet applications – ever tried an olive oil gelato or cookies and cakes made with oil? The distinct flavor of olive oil can add depth of flavor and a nice counterpoint to the sweetness of sugary treats and citrusy desserts. Lighter virgin oils are natural choices for cooking Mediterranean; what would paella, bouillabaisse, or a good pizza or pasta sauce be without the flavor of olive oil? If you’re just trying to get canola and other oils out of your diet, you can more or less replace them with refined olive oil without an issue – replacing butter may be less certain. Olive oil is also a perfect vector for imparting flavor in meat; mix up your own marinade and ditch the store-bought dressing for more flavor at a cheaper price.
Heart-healthy, great for vegans , Paleo-approved (unlike canola and other vegetable oils), diverse in quality and production process, possessed of a long and storied history, and just plain tasty, olive oil is a cooking choice no fledgling cook or foodie should be without. To get the good stuff, look in specialty stores – Dave’s Fresh Pasta is close by, while the North End is an olive oil goldmine. If you’re just looking to get your fix, any supermarket will have plenty, but Whole Foods and the like will usually have better selection than say, Shaws.
If you’re looking to wet your palate for olive oil, try these innovative oil applications:
Lemon Olive Oil Cake, for Adventurous Bakers
Olive Oil Mashed Potatoes, a Perfect Dairy-free Mashed Potato
Aioli; try making olive oil mayonnaise as per Kenji’s technique as well
Chicken D’Arduni, a perfect example of low-heat olive oil awesomeness