For most diners, there's no harm in indulging in french fries occasionally. Certain techniques and ingredients can even give the fried treat some nutritional value, like cooking them with heart-healthy olive oil. But olive oil does not offer the same temperature-control that vegetable oil affords, which can make it difficult to decide which product is the best choice for your homemade treat. Your choice ultimately depends on how you want to cook the fries and how indulgent you want to be.
Vegetable Oil for Temperature Control
One of the most critical aspects of frying oil is its smoke point, which is the temperature at which the fat starts to break down and the oil starts to smoke. The smoke point is the highest temperature oil can reach and still be safe and usable. It is best to use an oil with a high smoke point when frying food to ensure kitchen safety and the crispness of the fried surface. Vegetable oil has a much higher smoke point -- 453 degrees Fahrenheit -- than any olive oil. Extra virgin olive oil smokes at only 331 F while virgin olive oil smokes at 428 F. In terms of safety and your ability to achieve golden, crisp fries, vegetable oil is the best choice.
Olive Oil for Health and Nutrition
Olive oil is a monounsaturated fat, which raises good cholesterol levels and is essential in a well-balanced diet. It also contains helpful antioxidants, which combat free radicals in your body. Vegetable oil, on the other hand, generally comes from a combination of less healthful sources. In many cases, oils are chemically extracted from various plants yielding a concoction of trans fats, which are the least healthful type you can eat. In terms of health and nutrition, olive oil is the better choice.
Frying With Olive Oil
If you are shallow- or deep-frying french fries in olive oil, choose light olive oil, which is the type of olive oil with the highest smoke point. It yields a delicate crust rather than the hearty crunch that vegetable oil generates, but the nutritional benefits are worth the trade-off to most health-conscious diners. Choose filtered olive oil, which will have fewer of the green solids that are prone to burning at higher temperatures. The solids aren't visually perceptible, but the product's label should describe the oil as "filtered."
Oven-Frying With Olive Oil
If you want extra-crisp fries but also want to cook them in olive oil, oven-frying the potatoes may be your best option because it requires less oil and allows better temperature control. Soak the cut potatoes in water, rinse them, then pat them dry before cooking them to draw out excess starch, which allows them to develop a crispier texture. Lightly coat the pieces in olive oil, then spread them evenly on a baking sheet. Cook them in an oven preheated to a high temperature that is below the smoke point of the olive oil you are using -- 415 F to 425 F is a safe choice for virgin or light olive oil. Cook the fries until they are tender and slightly golden, then remove them from the oven. Let them cool, then return them to the oven at the same temperature. Cook them until they develop a richer golden hue. Double-cooking the potatoes and allowing them to cool in between generates crispier fries.
An alternative oil may be your best option if you want the temperature control that vegetable oil offers without the nutritional drawbacks. Second to olive oil, sunflower oil has the next highest level of monounsaturated fats, but it has a much higher smoke point. In fact, the smoke point of sunflower oil -- 464 F -- is even higher than the smoke point of vegetable oil. Canola oil has the third-highest level of monounsaturated fats as well as a high smoke point: 468 F. It is also as widely available and cost effective as vegetable oil.