Cooking oils are obtained from plant sources, such as seeds, nuts and beans. Their culinary uses are many. Since they are fats, oils provide flavor, richness, lubrication and are a means of browning foods.

When selecting oils, two considerations must be kept in mind: flavor and smoke point (the temperature at which heated oil begins to burn and decompose). An inexperienced cook may wish to have only two oils on hand. An all-purpose oil for sautéing and frying is a must. Choose a flavorless oil, such as soybean or safflower. Olive oil adds flavor to salad dressing and Mediterranean dishes. Purchase other oils only as you need them.

Corn oil has little flavor and a high smoke point. It is good for frying.

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.

Peanut oil has a faint peanut flavor and a high smoke point. It is a good oil for frying and stir-frying.

Safflower oil is flavorless and has a high smoke point, making it an ideal choice for frying.

Sesame oil is amber-colored oil pressed from toasted sesame seeds. It has a strong, nutty flavor that when used sparingly adds a unique flavor to foods, such as stir-fries, Asian noodles and fish dishes. It is not used for frying. There is also a pale-colored cold-pressed sesame oil that is available in health food stores. It is used for cooking and as a salad oil. The two types are not interchangeable.

Soybean oil has little flavor and a high smoke point. It is excellent for frying and is the most common cooking oil in the United States.

Walnut oil is made from walnuts. This expensive oil is usually imported from France. It has a pleasant nutty flavor and is often added to salad dressings. Look for it in large supermarkets and gourmet food stores. Buy walnut oil in small quantities because a little goes a long way.

Flavored oils are oils to which herbs, spices and seasonings, such as garlic and chili peppers, have been added. Use them when you need a quick burst of flavor.

Oils should be stored in a cool, dark place. Cold-pressed sesame oil is more perishable and should always be refrigerated. Oils will keep from three to six months. 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.