Common salt is a mineral substance; another example is the white scaly substance which sometimes forms on the inside of a teakettle or on any pan in which water has been heated. Soda is still another familiar mineral substance. The condiment salt--ordinary table salt--(see Condiments) must not be confused with the term "salts"; the latter applies to many mineral substances besides common salt.
USE OF ASH IN THE BODY.--Ash as well as water does not burn in the body. It is therefore considered an incombustible foodstuff. Bones, teeth, and many other parts of the body contain certain mineral materials. Ash helps to build the body.
Ash exists in the fluids of the body. For example, there is salt in perspiration and in all excretions of the body. The digestive juices also contain mineral materials, and ash aids in the digestive processes of the body. Scientists have shown that ash participates in many ways in the regulation of body processes.
Thus ash has two main uses in the body: (a) it aids in building the body; and (b) it aids in regulating body processes. Ash, therefore, is an absolute necessity in diet.
FRESH VEGETABLES.--It was mentioned above that fresh vegetables are one of the most valuable food sources of ash. The leaves, stems, pods, and roots of certain plants, and also those fruits which are used as vegetables, may be classed as fresh vegetables. Some of these are: cabbage, brussels sprouts, lettuce, water cress, spinach, celery, onions, tomatoes, cucumbers, beets, carrots, and turnips.
Fresh vegetables contain not only the foodstuff ash, but water. Indeed most fresh vegetables contain from 75 to 90 per cent of water.
In addition to these two foodstuffs, vegetables contain cellulose. The latter is a fibrous substance which forms for the most part the skins and interior framework of vegetables and fruits. The strings of beans and celery and the "pith" of turnips and radishes, for example, contain much cellulose.
Foods containing both ash and cellulose have a laxative effect. Hence the value of fresh vegetables in diet. The use of fresh vegetables cannot be too strongly urged. Certain vegetables, especially the green leaved vegetables, also contain substances which are necessary to make the body grow and keep it in good health (see Division Seven).
Most persons should use fresh vegetables more freely than they do.
SUGGESTIONS FOR COOKING GREEN VEGETABLES.--If ash is such a valuable constituent of vegetables, the latter should be cooked so as to retain all the ash. Unfortunately vegetables are not always cooked in such a way that the minerals are saved. Just as salt dissolves readily in water, so many of the mineral materials found in green vegetables dissolve in the water in which vegetables are cooked. Hence if it is necessary to drain off water from vegetables after cooking, it is evident there may be much loss of nutriment.
Ash is also one of the substances which gives flavor to vegetables. Insipid flavors of certain vegetables may be due to improper cooking.
A most important point to consider in the cooking of vegetables is the saving of the minerals. This can be accomplished in several ways:
1. Cooking in water with their skins.
2. Cooking in water and using the water which must be drained away after cooking for sauces and soups.
3. Cooking in such a small quantity of water that none needs to be drained away after cooking.
4. Cooking in steam.
5. Cooking in the oven by means of dry heat.
COOKING VEGETABLES IN WATER.--Water in which vegetables are cooked should be salted. Use 1 teaspoonful of salt for each quart of water. The water should be boiling when the vegetables are added and should be kept boiling gently during the entire cooking. Rapidly boiling water wears off the edges of vegetables and breaks them.
The water in which vegetables are cooked is called vegetable stock. When vegetables are pared or scraped before cooking in water, the stock should be utilized in making vegetable sauces.
Test vegetables for sufficient cooking with a fork or knitting needle.