Every good housekeeper should know approximately the composition of the various foodstuffs, and so be able to make proper combinations of foods and substitutions when necessary. Hunger and thirst are provided by nature as guides in the choice of food, and if the bodily conditions are normal, these, as a rule, are safe guides to follow.
The nutritive value of many foods depends upon how they are cooked. Many raw foods are indigestible, but these same foods cooked are nutritious. The importance of proper cooking cannot be overestimated. Cooking changes the food so that the digestive juices can take care of it; cooking improves the flavor and the appearance, thus making the food more appetizing; and cooking kills disease germs, parasites, and other dangerous organisms.
Proper cooking and dainty serving make even cheap foods more palatable. This stimulates the digestive juices; hence food should be made appetizing in order to obtain the greatest nutritive value from it.
METHODS OF COOKING
Boiling
Boiling point is the temperature at which a fluid is converted into vapor, with the phenomenon of ebullition. The boiling point of water is 212 degrees Fahrenheit. In cooking, the term boiling means the cooking of food in a boiling liquid, and water is the liquid generally used. Rapidly boiling water is no hotter than when the agitation is less, but in some cases, as in the boiling of rice, violently boiling water is recommended for the purpose of keeping the grains of rice separated. The boiling point of water once reached can be held with a moderate amount of heat.
Food is generally boiled by putting immediately into boiling water. This sears the surface, and keeps in the juices; but if the water is to be used for soups, gravies, and so forth, the food is put into cold water and brought slowly to the boiling point. Salt is added to the boiling water ordinarily when cooking food, as it tends to keep the flavor in the food.