33. The methods of cooking with moist heat, that is, through the medium
of water, are boiling, simmering, steaming, dry steaming, and braizing.
In every one of these processes, the effect of moist heat on food is
entirely different from that of dry heat. However, the method to be
selected depends to a great extent on the amount of water that the food
contains. To some foods much water must be added in the cooking process;
to others, only a little or none at all. If food is not placed directly
in large or small quantities of water, it is cooked by contact with
steam or in a utensil that is heated by being placed in another
containing boiling water, as, for example, a double boiler.
As water is such an important factor in cooking with moist heat,
something concerning its nature and use should be understood. Therefore,
before considering the moist-heat cooking processes in detail, the
function of water in the body and in cooking and also the kinds of water
are discussed.
34. FUNCTION OF WATER IN THE BODY.--Water supplies no energy to the body,
but it plays a very important part in nutrition. In fact, its particular
function in the body is to act as a solvent and a carrier of nutritive
material and waste. In doing this work, it keeps the liquids of the body
properly diluted, increases the flow of the digestive juices, and helps
to carry off waste material. However, its ability to perform these
necessary functions in the right way depends on its quality and
its safety.
35. KINDS OF WATER.--Water is either hard or soft. As it falls from the
clouds, it is pure and soft until it comes in contact with gases and
solids, which are dissolved by it and change its character. It is
definitely known that the last of the water that falls in a shower is
much better than the first, as the first cleanses not only the air, but
the roofs and other things with which it comes in contact. In passing
through certain kinds of soil or over rocks, water dissolves some of the
minerals that are contained there and is thus changed from soft to hard
water. If sewage drains into a well or water supply, the water is liable
to contain bacteria, which will render it unfit and unsafe for drinking
until it is sterilized by boiling. Besides rain water and distilled
water, there is none that is entirely soft; all other waters hold
certain salts in solution to a greater or less degree.
The quality of hardness, which is present in nearly all water, is either
temporary or permanent. Water is temporarily hard when it contains
soluble lime, which is precipitated, that is, separated from it, upon
boiling. Every housewife who uses a teakettle is familiar with this
condition. The lime precipitated day after day clings to the sides of
the vessel in which the water is boiled, and in time they become very
thickly coated. Permanent hardness is caused by other compounds of lime
that are not precipitated by boiling the water. The only way in which to
soften such water is to add to it an alkali, such as borax, washing
soda, or bicarbonate of soda.
36. USES OF WATER IN COOKING.--It is the solvent, or dissolving, power
of water that makes this liquid valuable in cooking, but of the two
kinds, soft water is preferable to hard, because it possesses greater
solvent power. This is due to the fact that hard water has already
dissolved a certain amount of material and will therefore dissolve less
of the food substances and flavors when it is used for cooking purposes
than soft water, which has dissolved nothing. It is known, too, that the
flavor of such beverages as tea and coffee is often greatly impaired by
the use of hard water. Dried beans and peas, cereals, and tough cuts of
meat will not cook tender so readily in hard water as in soft, but the
addition of a small amount of soda during the cooking of these foods
will assist in softening them.
Water is used in cooking chiefly for extracting flavors, as in the
making of coffee, tea, and soups; as a medium for carrying flavors and
foods in such beverages as lemonade and cocoa; for softening both
vegetable and animal fiber; and for cooking starch and dissolving sugar,
salt, gelatine, etc. In accomplishing much of this work, water acts as a
medium for conveying heat.
37. BOILING.--As applied to cooking, boiling means cooking foods in
boiling water. Water boils when its temperature is raised by heat to
what is commonly termed its _boiling point_. This varies with the
atmospheric pressure, but at sea level, under ordinary conditions, it is
always 212 degrees Fahrenheit. When the atmospheric pressure on the
surface of the water is lessened, boiling takes place at a lower
temperature than that mentioned, and in extremely high altitudes the
boiling point is so lowered that to cook certain foods by means of
boiling water is difficult. As the water heats in the process of
boiling, tiny bubbles appear on the bottom of the vessel in which it is
contained and rise to the surface. Then, gradually, the bubbles increase
in size until large ones form, rise rapidly, and break, thus producing
constant agitation of the water.
38. Boiling has various effects on foods. It toughens the albumin in
eggs, toughens the fiber and dissolves the connective tissues in meat,
softens the cellulose in cereals, vegetables, and fruits, and dissolves
other substances in many foods. A good point to bear in mind in
preparing foods by boiling is that slowly boiling water has the same
temperature as rapidly boiling water and is therefore able to do exactly
the same work. Keeping the gas burning full heat or running the fire
hard to keep the water boiling rapidly is therefore unnecessary;
besides, it wastes fuel without doing the work any faster and sometimes
not so well. However, there are several factors that influence the
rapidity with which water may be brought to the boiling point; namely,
the kind of utensil used, the amount of surface exposed, and the
quantity of heat applied. A cover placed on a saucepan or a kettle in
which food is to be boiled retains the heat, and thus causes the
temperature to rise more quickly; besides, a cover so used prevents a
loss of water by condensing the steam as it rises against the cover. As
water boils, some of it constantly passes off in the form of steam, and
for this reason sirups or sauces become thicker the longer they are
cooked. The evaporation takes place all over the surface of the water;
consequently, the greater the surface exposed, the more quickly is the
quantity of water decreased during boiling. Another point to observe in
the boiling process is that foods boiled rapidly in water have a
tendency to lose their shape and are reduced to small pieces if allowed
to boil long enough.
Besides serving to cook foods, boiling also renders water safe, as it
destroys any germs that may be present. This explains why water must
sometimes be boiled to make it safe for drinking. Boiled water, as is
known, loses its good taste. However, as this change is brought about by
the loss of air during boiling, the flavor can be restored and air again
introduced if the water is shaken in a partly filled jar or bottle, or
beaten vigorously for a short time with an egg beater.
39. SIMMERING, OR STEWING.--The cooking process known as simmering, or
stewing, is a modification of boiling. By this method, food is cooked in
water at a temperature below the boiling point, or anywhere from 185 to
200 degrees Fahrenheit. Water at the simmering point always moves
gently--never rapidly as it does in boiling. Less heat and consequently
less fuel are required to cook foods in this way, unless, of course, the
time consumed in cooking the food at a low temperature is much greater
than that consumed in cooking it more rapidly.
Aside from permitting economy in the use of fuel, simmering, or stewing,
cooks deliciously certain foods that could not be selected for the more
rapid methods. For example, tough cuts of meat and old fowl can be made
tender and tasty by long cooking at a low temperature, for this method
tends to soften the fiber and to develop an excellent flavor. Tough
vegetables, too, can be cooked tender by the simmering process without
using so much fuel as would be used if they were boiled, for whatever
method is used they require long cooking. Beets, turnips, and other
winter vegetables should be stewed rather than boiled, as it is somewhat
difficult to cook them tender, especially in the late winter and early
spring. If dry beans and peas are brought to the simmering point and
then allowed to cook, they can be prepared for the table in practically
the same length of time and without so much fuel as if they boiled
continuously.
40. STEAMING.--As its name implies, steaming is the cooking of food by
the application of steam. In this cooking process, the food is put into
a _steamer_, which is a cooking utensil that consists of a vessel with a
perforated bottom placed over one containing water. As the water boils,
steam rises and cooks the food in the upper, or perforated, vessel.
Steamers are sometimes arranged with a number of perforated vessels, one
on top of the other. Such a steamer permits of the cooking of several
foods at the same time without the need of additional fuel, because a
different food may be placed in each vessel.
Steaming is preferable to boiling in some cases, because by it there is
no loss of mineral salts nor food substances; besides, the flavor is not
so likely to be lost as when food is boiled. Vegetables prepared in this
way prove very palatable, and very often variety is added to the diet by
steaming bread, cake, and pudding mixtures and then, provided a crisp
outside is desired, placing them in a hot oven to dry out the
moist surface.
41. DRY STEAMING.--Cooking foods in a vessel that is suspended in
another one containing boiling water constitutes the cooking method
known as dry steaming. The double boiler is a cooking utensil devised
especially for carrying on this process. The food placed in the
suspended, or inner, vessel does not reach the boiling point, but is
cooked by the transfer of heat from the water in the outside, or lower,
vessel. A decided advantage of this method is that no watching is
required except to see that the water in the lower vessel does not boil
away completely, for as long as there is water between the food and the
fire, the food will neither boil nor burn.
Because of the nature of certain foods, cooking them by this process is
especially desirable. The flavor and consistency of cereals and foods
containing starch are greatly improved by long cooking in this way.
Likewise, custards and mixtures containing eggs can be conveniently
cooked in a double boiler, because they do not require a high
temperature; in fact, their texture is spoiled if they are cooked at the
boiling point. To heat milk directly over the flame without scorching it
is a difficult matter, and, on the other hand, boiled milk is hard to
digest. Because of these facts, food containing milk should not be
boiled, but should be cooked at a lower temperature in a double boiler.
42. BRAIZING.--Cooking meat in an oven in a closed pan with a small
quantity of water constitutes braizing. This cooking process might be
called a combination of stewing and baking, but when it is properly
carried out, the meat is placed on a rack so as to be raised above the
water, in which may be placed sliced vegetables. In this process the
meat actually cooks in the flavored steam that surrounds it in the hot
pan. The so-called double roasting pans are in fact braizing pans when
they are properly used. A pot roast is the result of a modification of
the braizing method.