: For a topical guide to this subject, see Outline of cooking.
in China s and green peppers on a skillet 'Cooking' is the process of
preparing food by applying heat, selecting, measuring and combining of
ingredients in an ordered procedure for producing safe and edible food. The
process encompasses a vast range of methods, tools and combinations of
ingredients to alter the flavor, appearance, texture, or digestibility of food.
Factors affecting the final outcome include the variability of ingredients,
ambient conditions, tools, and the skill of the individual doing the actual
cooking. The diversity of cooking worldwide is a reflection of the aesthetic,
agricultural, economic, cultural, social and religious diversity throughout the
nations, races, creeds and tribes across the globe. Applying heat to a food usually, though not always, chemically transforms it,
thus changing its flavor, texture, consistency, appearance, and nutritional
properties. Methods of cooking that involve the boiling of liquid in a
receptacle have been practised at least since the 10th millennium BC, with the
introduction of pottery. The most traditional clothing when cooking is aprons. Proteins Edible animal material, including muscle, offal, milk and egg white,
contains substantial amounts of protein. Almost all vegetable matter (in
particular legumes and seeds) also includes proteins, although generally in
smaller amounts. These may also be a source of essential amino acids. When
proteins are heated they become de-natured and change texture. In many cases,
this causes the structure of the material to become softer or more friable -
meat becomes cooked. In some cases, proteins can form more rigid structures,
such as the coagulation of albumen in egg whites. The formation of a relatively
rigid but flexible matrix from egg white provides an important component of much
cake cookery, and also underpins many desserts based on meringue. Liquids Cooking often involves water which is frequently present as other
liquids, both added in order to immerse the substances being cooked (typically
water, stock or wine), and released from the foods themselves. Liquids are so
important to cooking that the name of the cooking method used may be based on
how the liquid is combined with the food, as in steaming, simmering, boiling,
braising and blanching. Heating liquid in an open container results in rapidly
increased evaporation, which concentrates the remaining flavor and ingredients -
this is a critical component of both stewing and sauce making. Fat Fats and oils come from both animal and plant sources. In cooking, fats
provide tastes and textures. When used as the principal cooking medium (rather
than water), they also allow the cook access to a wide range of cooking
temperatures. Common oil-cooking techniques include sauteing, stir-frying, and
deep-frying. Commonly used fats and oils include butter; olive oil; vegetable
oils such as sunflower oil, corn oil, and safflower oil; animal fats such as
lard, schmaltz, and beef fat (both dripping and tallow); and seed oils such as
rapeseed oil (Canola or mustard oil), sesame oil, soybean oil, and peanut oil.
The inclusion of fats tends to add flavour to cooked food, even though the taste
of the oil on its own is often unpleasant. This fact has encouraged the
popularity of high fat foods, many of which are classified as junk food. Carbohydrates Carbohydrates include simple sugars such as glucose (from table
sugar) and fructose (from fruit), and starches from sources such as cereal
flour, rice, arrowroot, potato. The interaction of heat and carbohydrate is
complex. Long-chain sugars such as starch tend to break down into simpler sugars when
cooked, while simple sugars can form syrups. If sugars are heated so that all
water of crystallisation is driven off, then caramelization starts, with the
sugar undergoing thermal decomposition with the formation of carbon, and other
breakdown products producing caramel. Similarly, the heating of sugars and
proteins elicits the Maillard reaction, a basic flavor-enhancing technique. An emulsion of starch with fat or water can, when gently heated, provide
thickening to the dish being cooked. In European cooking, a mixture of butter
and flour called a roux is used to thicken liquids to make stews or sauces. In
Asian cooking, a similar effect is obtained from a mixture of rice or corn
starch and water. These techniques rely on the properties of starches to create
simpler mucilaginous saccharides during cooking, which causes the familiar
thickening of sauces. This thickening will break down, however, under additional
heat. Vitamins and minerals Vitamins are materials required for normal human
metabolism but which the body cannot manufacture itself and which must therefore
come from food. Vitamins come from a number of sources including fresh fruit and
vegetables (Vitamin C), carrots, liver (Vitamin A), cereal bran, bread, liver e
( B vitamins), fish liver oil (Vitamin D) and fresh green vegetables (Vitamin
K). Many minerals are also essential in small quantities including iron,
calcium, magnesium and sulphur; and in very small quantities copper, zinc and
selenium. Micronutrients from fruit and vegetables may be destroyed or eluted by
cooking. However, research led by Dr Sue Southon of the Institute of Food
Research in Norwich has found that cooking vegetables facilitates the absorption
of micronutrients. Cooked food may therefore provide more health benefits than
raw food.[http://news.bbc.co.uk/1/hi/health/359175.stm] Vitamins from fresh vegetables and fruit may be destroyed or eluted by cooking
and the greatest benefit is derived from uncooked material. Vitamin C is
especially prone to oxidation during cooking and may be completely destroyed by
protracted coking. Minerals may also be eluted by extended boiling.
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