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Cooking Oil Questions


Heart-healthy olive oil comes in several different varieties.
Heart-healthy olive oil comes in several different varieties.
©Photodisc

Q. Is olive oil really good for you? I know there are several different types -- what are the differences among them?

A. Olive oil is one of the good guys. In our fat-phobic society, few people like to concede that there actually are fats that are good for us. However, research has shown that for all the bad fats that put us at risk for heart disease, there are also good fats that actually protect us from disease.

A diet that includes good fats such as olive oil can protect your heart by raising your HDL -- the beneficial cholesterol that helps remove the LDL, or "bad" cholesterol, from your blood -- without raising your total cholesterol level. Olive oil is of course a mainstay of the Mediterranean diet, which has been shown to be one of the most healthful diets in the world.

There are several types of olive oil. Most can be used interchangeably, but once you've learned to appreciate the flavor differences, you will be hard-pressed to use just any ol' olive oil. Almost all of the domestic varieties of olive oil are grown and harvested in California; imported varieties come from Italy, Greece, France, and Spain. The color and flavor can vary, depending on the type of olive, where it's grown, and under what conditions.

Olive oils are graded according to their acid content. The best olive oils are "cold-pressed," meaning that the oil is extracted by exerting pressure on the olives. This results in a naturally low acid content. Oils that have not been obtained through cold-pressing have been extracted through a chemical or steam process.

Extra virgin olive oil is the oil from the first pressing, with an acid content of 1 percent. All domestic extra virgin olive oil is cold-pressed; only about half of the imported extra virgins are cold-pressed. Extra virgin is considered the best olive oil because it's the most flavorful; it is also the most expensive. Virgin olive oil is also from the first pressing, but has a higher level of acidity, about 2 percent.

The flavor of extra virgin and virgin olive oils tends to break down at high heat, so use them when you want maximum olive flavor, such as in salad dressings, in soups and stews, and for dipping. Use other, less expensive olive oils for frying.

Fino olive oil is a blend of extra virgin and virgin. Oil that's labeled simply "olive oil" or "pure olive oil" is a blend of refined olive oil and virgin or extra virgin olive oil; it's higher in acid, making it better for frying due to its higher smoke point.

Olive oil should be stored in a cool, dark place, where it will keep for about six months. It also can be stored in the refrigerator; chilled olive oil turns cloudy, but that condition is easily reversed by returning the oil to room temperature.

Q. I'm trying to count calories and have been wondering: What is "light" olive oil?

A. Light olive oil is a relatively new variety of olive oil. Its light color and flavor result from a special filtration process. Light olive oil contains just as many calories and total fats, including the beneficial monounsaturated fats, as regular olive oil; "light" refers to its lighter color and flavor. Because of its light flavor, it is useful in baking and cooking dishes where regular olive oil would be too heavy or flavorful.

Light olive oil also has a higher smoke point than regular olive oil, meaning it can be used in frying over high heat.

Q. How do I store oil and for how long?

A. Oils will keep from three to six months when stored in a cool, dark place. If a cool spot is not available they should be refrigerated. Buy small quantities of oils that you use infrequently. Heat, light and time will turn oils rancid. A rancid oil will ruin any dish it is used in.

Q. What is the difference between extra virgin, virgin and just plain olive oils?

A. Olive oil is produced when tree-ripened olives are pressed. The best olive oils are extracted using a chemical-free process. They can be classified as extra-virgin or virgin. Both are cold-pressed oils from the first pressing of the olives.

Extra-virgin has a lower acidity and a full-bodied fruity flavor. It is the most expensive of olive oils. Use it when the fruity flavor will lend a pleasing note to foods, such as in salad dressings, for dipping bread and in vegetable dishes.

Products labeled olive oil are an all-purpose blend of olive oils. They are less expensive and blander in flavor, making them an economical choice for most uses. Light olive oil is olive oil that has been filtered to make it lighter in flavor. Filtering also increases its smoke point making it a good choice for sautéing and pan-frying.

Q. Can I substitute applesauce for oil in baking recipes? What is the correct ratio?

A. The recipes best suited for substituting applesauce in place of oil are recipes for quick breads, muffins, and other moist, cake-like baked goods. These products -- unlike cookies, which require the addition of butter for flavor and texture -- can effectively be made using applesauce without much sacrifice in taste.

If this is your first time making a low-fat version of a baking recipe, you may want to substitute only half the amount of oil with applesauce. Otherwise, substituting all of the oil with applesauce using a 1-to-1 ratio is perfectly acceptable.

When adding the liquid ingredients to the dry ingredients, do not overmix, as reduced-fat recipes have more of a tendency to become tough when baked. Baked goods made with applesauce may be slightly moister and denser than original oil-based recipes, but remember to bake until just done (when a toothpick inserted near the center of the product comes out clean). Dry, over-baked goods are never appetizing.

For more tips on cooking with oil, see:


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