Understanding Cooking Methods
Understanding Cooking
We have two ways we can cook food, the two types of heat used for cooking are moist and dry method.
Moist Heat Method -
Blanching
Braising
Poaching
Boiling
Steaming
Dry Heat Method -
Baking
Grilling
Barbecuing
Roasting
Sautéing
Cooking can improve the safety of foods by breaking down toxins that are in some foods that otherwise would be harmful if we eat them raw. Making the food more palatable, cooking also makes some foods easier to digest while also destroying bacteria and harmful organisms in the foods. Environmental pollutants are removed when food is cooked as well as making phytochemicals more available in some foods. More presentable, more palatable and tasty foods encourage us to cook foods in many different ways.
Examples of how cooking affects foods -
B group vitamins in meats When you cook meat, you lose a large amount of B group vitamins especially thiamine. B group vitamins leach into water and most are heat sensitive and will be destroyed by cooking. The more time, the higher the temperature you cook the meats, the greater the loss of B group vitamins will be.
Connective tissues Should you use a moist cooking method, this would start the process of converting the collagen into gelatine. Collagen, the protein of connective tissue is not affected by heating the food. Braising can help soften the connective tissue making it softer and easier to eat.
Fats Fat soluble vitamins can be lost when roasting meat if you do not use the juices from the meat in the tray. Dry methods of cooking do not cause any loss of fat on the meat. When heated up to high temperatures, oils and fats create trans-unsaturated fatty acids. These trans fats damage the cells in our bodies so consider the oils you are using and temperature. Some oils like coconut oil and rice bran oil have a higher smoke point than others, which are better for cooking. Heat up your pan, have foods ready and place oil in pan only when you are ready to cook to reduce the oils heating time.
Mercury in fish Cooking fish doesn’t seem to have an effect on the mercury content of fish. Pollutants can be trapped in your fish if you deep-fry to seal it within. Mercury is in the muscle tissue but trim the fat from the fish can reduce the pollutants slightly.
Mineral content of braised foods The nutrients from the food could leech but the essential trace minerals are not affected by braising food. High temperatures help trap the nutrients within the food.
Vitamin B and cooking
Being water soluble, the B vitamins will leach into water when cooked. The degradation by air and light is a very slow process and does not or is unclear if it affects all the B group vitamins. Cooking food with B3 (Niacin) can actually improve the availability of niacin. Thiamine (B1) and Folate (B9) are the most unstable B vitamins to be destroyed by cooking.
One way to cook B group vitamins that I would use is steaming. This does not require you to add any oils or fats to the food. However as this is not a dry method, some water-soluble vitamins can still leech out into the steaming water. The temperatures are much lower than a lot of other cooking methods, which therefore do not affect those B group vitamins sensitive to heat as dramatically. There is less time required in cooking the foods also which helps with nutrient retention. If you don’t want to lose any nutrients, you can use the cooking water from steaming, boiling etc in other cooking like soups, slow cooking, stews, and gravy for example.
When cooking things like rice and quinoa, I use the absorption method so there is no water left over when you finish cooking, this way any nutrients the leach out go back into the foods you are cooking.
Another way to help with retaining the nutrients could be washing and scrubbing vegetables and leaving the skin on, less water when boiling, cook the food in less time or at a lower heat. If you don’t want to use steaming, try roasting /baking or grilling or microwaving before using water-submerged method to retain as much B group vitamins as you can.
When baking, you can wrap vegetables in foil like potato with skin on. This will allow the steam the potato creates to speed up the cooking and doesn’t add moisture. The water soluble nutrients will be perserved just below the surface level of the skin.
Many of use cut up vegetables before cooking, speeding up the cooking process but in the process we creat more surface area for the nutrients to be lost. Cut your pieces larger or leave whole where possible to help with maximising nutrients in foods.
Cooking methods
Blanching A method of putting food in boiling water for a short period of time and then quickly transferring to icy water to stop the cooking process. This gives vegetables a more vibrant colour and removed the bitter taste. Cooking at high heat will soften vegetables and help kill microorganisms. Vitamin C and B group vitamins are destroyed easily being water soluble vitamins being heat sensitive so be careful not to cook too long.
Baking Baking is a cooking method applying air flow and dry heat that is effective in breaking down starches. As it is dry heating, there is no leaching of nutrients from the food. You do however have negative effects on the nutrients from the long cooking times and nutrients affected by heat are destroyed. If baked goods leach fats or lose moisture, this will in turn result in loss of water soluble nutrients.
Braising This is like baking food but with liquid beneath the food or by placing the food in the liquid. With the high temperatures it creates steam using steaming and baking cooking methods. The connective tissue is softened by this method of cooking. High cooking temperatures can seal in the nutrients but heat-liable nutrients can leach out early in the cooking.
Poaching and boiling Poaching is gently heating food in water with vinegar or citrus juice. This affects vitamin K, and the water soluble B group vitamins, which need to be cooked below 100 degrees C. As poaching is a lower heat, they should remain in the food.
Grilling A dry heat method of cooking with the application of direct heat to the food. The food cooks quickly which helps in retaining the nutrients being lost, however heat-liable nutrients are lost from the food. Fat soluble content drips away with some calories as cooking leaving a plesant taste.
Pressure Cooking Increased pressure while cooking requires less cooking time. The liquids remaining in the pot contain the nutrients as it is hard to lose them with the steam trapped inside. Heat-liable nutrients are affected by pressure cooking foods.
Roasting Dry heat cooking of meats and vegetables at high temperatures using a fatty agent to assist with the cooking process like butter, oil, ghee and lard. Heat liable nutrients are lost with minerals remaining in the food.
Steaming Cooking without any oils or fatty agents with a small amount of water below to create steam for cooking. This allows vegetables for example to gain a rich colour and taste. Steaming is reasonably quick cooking without a complete loss of Vitamin C and B group vitamins. The cooking temperature is lower so you don’t loss as many nutrients but water-soluable nutrients are still affected.
Sauteing This is the method of shallow frying foods quickly with a coating of some kind of fatty combination or oil etc. If you are cooking rapidly the nutrients are sealed in but heat liable nutrients can still be lost but minerals remain.
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