Vegetables include nearly all kinds of plant food except fruits, grains and nuts.

Classification

Vegetables are classified as -Legumes - as peas, beans and lentils. Roots and Tubers - as potatoes, beets, turnips, etc. Green Vegetables - as lettuce, spinach, celery, etc. Composition. All vegetables have a high percentage of water, and with the exception of legumes, a relatively small proportion of protein. The chief nutrients are starch and sugar. The fats are usually small in amount and chiefly in the form of oils. A variety of mineral salts are present, chiefly salts of potash and soda united with organic acids. Vegetables give bulk to food and possess antiscorbutic properties.

Digestibility

As the gastric ferments play no part in carbohydrate digestion, vegetables are digested mainly in the intestines. The presence of cellulose prevents the ready digestion of the nutrients, hence it may be stated as a general rule that vegetable food is less completely digested and absorbed than animal food. It would seem desirable to restrict this type of food for persons of very weak digestive powers.

General Rules For Cooking Vegetables

Wash thoroughly; pare, peel, or scrape, according to the kind. Let them stand in cold water until ready to cook, to keep them crisp, to freshen them when wilted, or to prevent them from turning dark.

Cook in enough freshly boiling salted water to cover, and keep the water boiling (not rapid boiling, as tender vegetables are easily broken). Allow one teaspoon of salt to one quart of water. Salt may be added when vegetables are put in, except in the case of delicate green vegetables, as peas, spinach, etc., when it should not be added until nearly done. To preserve the color, cook green vegetables uncovered.

Vegetables should be cooked only until tender, drained immediately, and served promptly. Overcooking injures their flavor and makes them tough. Time for cooking vegetables varies with the size, age and freshness.

Legumes

Of this class of food-stuffs, peas and beans are the most important. Lentils and peanuts are also valuable, but less widely used.

Composition

Fresh legumes, such as peas and beans, contain from 2 per cent. to 9 per cent. of protein, a trace of fat and from 7 per cent. to 30 per cent. of carbohydrate.

Dried legumes, such as dried peas and beans, on account of the lessened amount of water, contain from 18 per cent. to 35 per cent. of protein, over 1 per cent. fat, and as high as 65 per cent. carbohydrate. They form one of the chief sources of protein in a strictly vegetarian diet.

Digestibility

Digestibility depends largely upon the method of cooking and the amount eaten. The more the cellulose is softened or removed, the more completely they are utilized. Legumes are apt to produce fermentation, which causes flatulence and gastro-intestinal disturbance. They are more suitable for those leading an active outdoor life than for invalids, convalescents, or those of sedentary habits.

Principles Of Cooking

The attractiveness and digestibility of dried legumes depends very greatly on proper cooking. Hard water must not be used, as it makes them hard and unpalatable, and causes a considerable loss of protein. "Water softened by boiling is more desirable than that softened by baking soda. When cooked in the former, the dried legumes, especially beans, keep their shape better, are only very slightly colored yellow, and are more mealy, consequently more digestible, as the digestive juices can more easily mingle with the particles of the food.