How many times have you walked into a gourmet food market and marveled at the many different olive oils on the shelves? If you are like most folks, you have one bottle at home that you use for pretty much every dish. Perhaps you have two, the second being in a beautiful bottle that decorates your kitchen counter or shelves and which you never got around to using.
Olive oil is an important ingredient of any dish that calls for it and there are reasons for using a particular one over another. In choosing the right olive oil for a dish that you are preparing, I believe that there are three factors that you should take into consideration: the heat level, if any, that you are going to apply because of the recipe's requirements; the geographic/cultural origin of the dish that you are preparing; and your own personal taste.
Application of heat to olive oil reduces the fruity character of the oil and at some level alters the chemical structure of the oil. Olive oil, unlike seed oil, remains stable in its chemical structure at relatively high temperatures because of its antioxidant and high oleic acid content. Research has shown that most pure olive oils have "smoking points" (the point at which the chemical structure of fats and oils is changed) ranging from 406º to 468º Fahrenheit. Extra virgin olive oils have a smoking point of approximately 300º Fahrenheit. The fruity flavor of the oil begins to erode at approximately 150º Fahrenheit.
This leads some people to believe that an inexpensive olive oil without regard for its organoleptic qualities may be used to prepare a heavily cooked dish. One interesting scientific argument, however, underlies the opposing culinary philosophy that the quality of your culinary creation is a reflection of the quality of the ingredients. During the application of high heat, cooking fat replaces part of the water content of the food that naturally evaporates during the cooking process. Although heat erodes the fruity flavor of olive oil, researchers have concluded that a deep cooking process, such as frying, with olive oil will inevitably impart a degree of flavor to the food. The point at which olive oil begins to penetrate the food, however, is later than other oils. Sixty percent (60%) of a food's moisture content must evaporate before olive oil begins to significantly penetrate (as opposed to coat) food. Other fats penetrate the food more quickly. (This is one reason why foods fried in olive oil will taste less greasy and will be lower in calories than foods fried in other fats). But the issue is whether you want to use a different olive oil for heavy cooking than other uses, and one answer may be that you want to use a good quality olive oil for cooking that will have a desirable texture, odor and taste, but not necessarily one with a fruity flavor that will inevitably be reduced through the application of heat.
Words frequently used by members of the International Olive Oil Council in their official tastings to describe organoleptic qualities which rate for odor and taste include: almond, apple, bitter, metallic, muddy-sediment, musty-humid, old, pungent, rancid, rough, soapy, sweet, vegetable water, and winey-vinegary. Therefore, I use a good quality olive oil for cooking that may not necessarily possess a fruity flavor, but most certainly does not possess the undesirable qualities lest they be imbued into the flavor of my dish.
Cost of an olive oil is not necessarily a true reflection of quality. Quality includes considerations of texture; the production process including the use or absence of chemicals to fertilize, reduce weeds or to reduce the oil acidity (to qualify for extra virgin label); scrupulous/unscrupulous mixes of olive oils and oil storage. Note that the foregoing discussion of quality components did not have to include flavor, therefore a good quality olive oil that is not necessarily fruity and flavorful can be used in cooking and baking to produce a good result without paying a high price for the oil.
I bake bread for the evening meal every day using olive oil, regardless of whether it is olive bread or Parmesan and garlic flavored breadsticks or flatbreads such as foccacia with tomatoes, rosemary and garlic. In my experience, the texture of the bread is vastly improved with a good quality olive oil and a poor quality olive oil will lend an undesirable flavor to the finished product. Olive oil added to the dough ingredients not only contributes to the flavor of the bread flours but it coats the gluten proteins thus tenderizing the resulting dough by reducing the amount of gluten formed. It also produces a more moist bread and slows down the deterioration of the dough. In addition, it increases the ability of the dough to trap gas, thus helping the dough to rise and increase in volume.
Geographical / Cultural Origin:
Your olive oil selection should also take into consideration the origin of the dish that you are making. Every dish / recipe originates from some specific region of the world. Such a dish was developed based on the nature and intensity of the flavor as well as the texture of the ingredients that are found in that region. You may wish to adhere to the qualities of the olive oil used by the creators to complement the dish taking into consideration the flavor, intensity and texture of the oil. I try to select an oil that does not necessarily have to come from that region, which in my opinion would be the ideal, but would be similar to the ones that are produced in that region.
A fresh Greek salad with feta and beautiful vine-ripened tomatoes works well with an unfiltered, richly textured oil. Fresh mozzarella, basil and tomatoes go well with a lighter, fruit and herb-flavored oil. Appetizers such as crudités, mezedes, or antipasti may be complemented by a very bold, tangy oil that was freshly pressed and stands out amidst strongly flavored meats and vegetables.
You are the ultimate artistic creator and arbiter of taste. The chef's choice of olive oil used in its raw form for salad dressings, marinades and conserves (such as for roasted red peppers, artichokes, fresh olives, cheese and sun-dried tomatoes) enables the chef to create the ambience of the dish. Your expression of what you would like to share with others should never be constrained by what others do or think should be done.
Use these guidelines when choosing an olive oil for any recipe. Consider what the recipe calls for, but never be afraid to try something different. Trust your sense of taste and explore the wonderful world of olive oil.