Regular olive oil vs. extra-virgin olive oil: What's the difference, and which should I use?
There are actually four kinds of olive oils.
Extra-virgin olive oil is typically produced from the first pressing of olives -- making it the most pure and least acidic (less than 0.8 percent), and the best tasting. Because it's expensive, heavier, and more flavorful than other types of olive oil, it’s best used as an accent to dishes (drizzled over bruschetta or for this Minty Quinoa Tabouleh), or in dressings and vinaigrettes, like this Tomato-basil Vinaigrette. Hint: Look for bottles that say “cold press” on the label. If it’s not cold-pressed, the heat from the extraction process changes the chemistry and quality of the olive oil.
Virgin olive oil isn't blended with other oils but has a higher acidity -- up to 2 percent. It's perfect for garnishing this Crema di Pomodoro (that's fancy Italian for "tomato soup" -- and it's awesome hot or cold).
Pure olive oil or olive oil is a blend of refined pomace oil and virgin olive oil. Pomace is produced by processing the leftovers of the virgin olive oil extraction. The blend (which usually contains as little as 5 to 10 percent virgin olive oil) is cheaper to produce. It doesn’t have as strong a flavor as virgin olive oils and is best suited for frying and cooking, or even as a less expensive substitute, like in this Orange/Olive Oil Cake.
Light olive oil isn't lower in fat -- it simply means the oil is made from refined olive oil. Bottles labeled “100 percent pure olive oil” are often the lowest quality.
Food Nerd Fact: Just like wine, several European countries have “name place” designations for olive oils, indicating not only the region where the olives were grown and where the oil was produced, but also denoting a higher level of standards and quality. If you see “DOP” (Denominazione d’Origine Protetta) on olive oil from Italy or the European Union, “AOC” (Appellation d’Origine Controlee) on French olive oil, or “DO” (Denominacion de Origen) on olive oil from Spain, it's generally considered to be a better olive oil.
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