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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
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.[citation needed]
A person who cooks as a profession is called a chef
Cooking prevents many foodborne
illnesses that would otherwise occur if the raw food was
eaten. Also, cooking increases the digestibility of some foods such as
grains. But in most cases if not cooked properly food can lose its
flavor as well as its nutrients.
These foods 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.
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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.
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.
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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 caramelisation
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.
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Cooking methods
.
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