Home cooks can effortlessly choose among baking, grilling or frying. Each method has its individual benefits and drawbacks, and what you choose may depend on the type of food you make as well as time considerations. Overall, stir-frying, when done properly, leads to fewer carcinogens produced, more retained nutrients and less added fat. Stir-frying is only one method of frying food, however.
Baking is often taken to mean roasting, which cooks meat, fish and vegetables at high temperatures in the oven. A dry-heat cooking method, baking requires little added fat, and if you use a roasting rack, any fat will drain out during cooking. Baking can destroy heat-sensitive vitamins, including vitamin C and some B vitamins. If you use fluids, such as stock, during the cooking process, water-soluble vitamins may be lost unless the liquid is consumed with the foods. Because baking exposes foods to high cooking temperatures, above 300 degrees Fahrenheit, acrylamide, a carcinogen is produced as the food browns. To avoid this, try lower roasting temperatures, although this will increase the cooking times.
Grilling is also a dry-heat cooking method that uses little added fat. Flavor is added to the foods as they are exposed to smoke and char during the cooking process. The high cooking temperatures, charring and exposure to smoke, however, means that grilled foods are high in carcinogens, namely heterocyclic amines and polycyclic aromatic hydrocarbons. As with baking, grilling will partly destroy heat-sensitive vitamins, although there is little loss of water-soluble vitamins.
Frying, including deep-frying, pan-frying and stir-frying, involves the use of added fat that browns the food. Deep-frying and pan-frying both involve submerging food in hot oil, while stir-frying uses a small amount of added oil and high heat to quickly cook foods. All three forms of frying lead to no water-soluble vitamin loss, and very few heat-sensitive vitamins are lost. As well, if you use a healthy oil to fry with, such as soybean or olive oil, you can boost your intake of healthy fats and vitamin E. Deep-frying and pan-frying are less healthy than stir-frying because they lead to a high absorption of added fat and the formation of acrylamide.
Cooking Technique and Food Choices
Proper technique is important to keep all cooking methods healthy. If your oil is not hot enough for deep- or pan-frying, then a crispy outer shell will not form around the foods, and it will take longer for the foods to cook, leading to extra absorbed oil. Similarly, if your grill is not hot enough before cooking, it can take longer for foods to be ready, leading to more smoke exposure, increasing the amount of carcinogens on your grilled foods. Add a bit of water to the bottom of the roasting pan when baking, to avoid smoke being produced during high temperatures. While all meats, fish, shellfish and vegetables can be cooked by baking, frying or grilling, dough products, such as breads, are better suited to baking, and eggs are better suited for frying or baking than for grilling.
- Nestle Professional Nutrition Magazine: Cooking Methods
- National Cancer Institute: Chemicals in Meat Cooked at High Temperatures and Cancer Risk
- Beyond Vegetarianism: Effects of Cooking on Nutrients
- Joy of Cooking; Irma S. Rombauer et al.
- How to Cook Everything Vegetarian; Mark Bittman