FOOD N° 2 6 / 06 CONTENTS • Moist-heat cooking methods COOKING – Boiling – Poaching – steaming METHODS – stewing/Braising – Pressure cooking – Microwave cooking • Dry-heat cooking methods – Roasting – sautéing – grilling – Baking • Fry-cooking methods – deep-frying – Pan-frying – stir-frying/Wok 2 COOKING METHODS • When practical, save the cooking Steaming: Moist-heat liquid for use in stocks, sauces and Cooking at a temperature of about casseroles. 100°C (212° F) in steam, with the food cooking • To add vitamins, sprinkle some and cooking liquid completely sepa- fresh herbs onto the cooked food. rated. You can use a commercial methods steamer or a pot with a rack that suspends the food above a small Generally, moist-heat cooking meth- amount of simmering liquid. ods use a liquid for cooking – usually Tips: water, stock or steam. The advan- • Use a flavoured liquid like stock, tage of steam is that it transfers more wine, water infused with herbs, heat at the same temperature. As a lemon, etc. result, the food cooks faster and fewer nutrients are lost. The cooking temperature may vary from 70° – 120° C (158° – 212° F). These methods Poaching: are particularly suitable for prepar- Cooking in liquid at a temperature ing pasta, rice, pulses and vegeta- under the boiling point (75°– 95° C/ bles. The methods referenced below, 167°– 203° F). though not exhaustive, are the more Tips: common techniques. • Not ideal for nutrient retention in vegetables and potatoes, because a Stewing / Braising: long cooking time results in addi- Meat is often browned before liquid Boiling: tional nutrient loss through osmosis is added. Meats and vegetables can Cooking in a lot of liquid at a tem- (nutrients boiled out into the liquid). be cooked or steamed in their own perature of about 100° C (212° F). • Use a pot with a large diameter. juice. A particular way of stewing Tips: • If possible, add herbs or spices to is to glaze: vegetables (carrots, small • Generally use as little water as the poaching liquid rather than salt onions) become covered with the possible to minimize the loss of or sugar. stew stock, which is reduced and vitamins and minerals. enriched with a little sugar. GOOD TO KNOW Blanching Purpose: • Deactivation of enzymes • Preservation of the colour • Killing of microorganisms that may be present GOOD TO REMEMBER Note: loss of about 20 – 30% of vitamin C, but vitamin retention improves Moist-heat cooking methods during subsequent storage (chill- Food Nutrition freeze process). + – Tips: Boiling • food (e.g. vegeta- • no fat / oil is needed • great loss of nutrients • Drain and refresh in cold or iced bles) for soups; (osmosis) e.g. water- water immediately to prevent fur- hot pots soluble vitamins ther vitamin loss through cooking. • starches such as (folate, vitamin B1, C) • Do not leave the food in the water rice, potatoes and as this will cause further loss of pasta nutrients through osmosis and will Poaching • meat with little • no fat / oil is needed • great loss of nutrients soften the texture of the food. connective tissue Note: Osmosis: Nutrients in food leak • eggs, fish, poultry, or diffuse to liquid with lower con- small sausages centration. Therefore, it is important Steaming • vegetables, fish, • nutrient-friendly to use this liquid for the sauce or as – • potatoes method stock for soups because it is rich in • minimal loss of vitamins and minerals. vitamins NutriPro Food 6/06 3 Cooking Methods Tips: Tips: • Use leftover water for the sauce • It is important to keep to the exact GOOD TO KNOW or as stock for soups. cooking time, as the food over- Phytochemicals • Use a pot with a tight-fitting lid cooks very quickly. (as wide and flat as possible). • Suitable for producing large batches The term phytochemicals refers to a (portion by portion) of food (vegeta- class of substances (at the moment 60 000 – 100 000 are known), which Pressure cooking: bles, potatoes, fish), or for producing exist only in plants. They are classi- Cooking in an airtight pressure a smaller amount of food (e.g. for fied into several groups (e.g. carote- cooker at about 105° – 120° C diet recipes). noids, flavonoids, phytoestrogens, (221° – 248° F). glucosinolates) and rated as health- Note: higher temperature equals supporting substances. They have, shorter cooking time. The steamer is for example, antioxidant, anti-carci- also suitable for blanching, poaching nogenic and anti-inflammatory and reheating. effects and may also reduce blood cholesterol. These effects can only be verified when the phytochemi- cals are obtained from whole foods in fruits and vegetables. Their effect when taken as supplements cannot currently be verified. Their loss dur- ing cooking varies greatly. Some are soluble and sensitive to heat and air; others are better obtained from well-done foods (lycopene in cooked tomatoes). Tip: The best way to serve a variety of phytochemicals is to create a diet that includes every colour of the rainbow (red, orange, yellow, green, blue/violet). NutriPro Food 6/06 – NESTLÉ PROFESSIONAL Nutrition Magazine 4 COOKING METHODS GOOD TO KNOW Microwave cooking: Cooking with electromagnetic waves, Dry-heat cook- How does a microwave either with or without a small amount ing methods work? of added liquid. The food can be In other cooking methods food browned or given a crust only if com- warms up from the outside in. But bined with a dry-heat method such Heat is transferred through air or fat. with the microwave, the heat comes as grilling. It is ideally suited for The cooking temperature is between from inside the food, from its water reheating food. 120° – 150° C (248° – 302°F), and for molecules. The electromagnetic Tips: short periods up to 300°C (572° F). waves of the microwave cause these • The food may cook unevenly and Suitable for foods rich in proteins, water molecules to vibrate and have hot and cold spots. like meat, fish and seafood and the resulting heat cooks the food. Note: where a crust is desired. Deciding factors for determining – For liquids: stir about halfway the required cooking time of certain through the cooking time to dis- Roasting: products can be water content, tribute heat more evenly. Cooking with browning on the stove molecular density, the starting tem- – For solid food: let sit for several or in the oven with or without perature of the food, as well as the minutes after cooking or reheat- adding fat, at a temperature of penetration or strength of the rays ing, before serving. 140°– 200°C (284°– 392° F). A special (normally 2 – 4 cm). According to • If the thickness of food (e.g. piece of form of short roasting is sautéing. current findings there is no risk of meat) is more than the penetration Tips: radiation exposure if microwave of the microwaves, there is a risk of • Important: roast at intense heat to ovens are used properly. the core remaining raw. As a result, seal the juices inside the meat, any existing microorganisms (e.g. then cook at low heat until done. salmonellae in poultry) may not be This reduces the loss of vitamins, killed. minerals and moisture. • Frozen products do not conduct • Use vegetable oils that are high in heat well, so there is a risk of the polyunsaturated or monounsaturat- outside area overheating while the ed fats like canola oil and sunflower inside remains raw. oil. Roast meat in its own juice. Note: defrost on low heat and cook • Brush vegetables with a minimum immediately. of oil to decrease fat absorption • Suitable dishes: glass, porcelain, during cooking. and microwave-safe plastic dishes. • For a low-fat meal: do not serve or eat the crust as it contains the roast’s fat. Remove the dark brown or black crust before eating, as it could con- tain carcinogenic (cancer-causing) substances. GOOD TO REMEMBER • A special method: cooking at a low temperature – cook the meat at a Moist-heat cooking methods temperature between 68°– 80° C Food Nutrition (154,4°– 176°F) in the oven until + – done (up to 24 hours). • vegetables (e.g. • vitamin and mineral • addition of some fat Stewing/ • Roasting in the pan or grilling bet- filled vegetables), retention if cooking if used for cooking or Braising ter preserves the vitamins and fruits liquid is kept for fur- fat released from minerals in meats, fish or chicken ther use meat during cooking • fish, meats (with than roasting in the oven or boiling, which is then ab- more connective • light cooking method due to heat, cooking time and loss sorbed by the sauce tissue) • nutrient-friendly of nutrients. method • heat-sensitive vita- mins are partially • minimal loss destroyed of vitamins Pressure • see boiling, • comparable with – cooking steaming, stewing steaming and stewing • reheating • less cooking time Microwave • any kind of food • minimal loss of vita- – cooking but only in small mins and minerals quantities • short cooking time NutriPro Food 6/06 5 Cooking Methods Sautéing: • Place food on a rack so fat can GOOD TO KNOW Dry-heat cooking method in which drain.When using a grill plate sim- heat is conducted by a small amount ply brush the plate with a mini- Cook & Chill of fat (the food is kept in motion). mum of oil (polyunsaturated or mo- Tips: nounsaturated vegetable oil) before Cook & chill is a food preparation system, not a cooking method. • Use for tender cuts of meat and heating. Never grill cured (pickled) The principle: the food is cooked to vegetables. meat, because cancer-causing 90 – 95% (depending on the system of • If meat is marinated, dry before substances (nitrosamine) may be regeneration/reheating), and all of cooking to ensure proper browning. formed. the cooking methods described here • Cook only single layers, don’t over- • Avoid overly moist marinades or may be used, except grilling.