Page:The Boston cooking-school cook book (1910).djvu/24

 animal foods (excepting fats and glycogen) and some vegetable foods. Examples: milk, cheese, eggs, meat, fish, cereals, peas, beans, and lentils. The principal constituent of proteid food is albumen. Albumen as found in food takes different names, but has the same chemical composition; as, albumen in eggs, fibrin in meat, casein in milk and cheese, vegetable casein or legumen in peas, beans, and lentils; and gluten in wheat. To this same class belongs gelatin.

The chief office of the carbohydrates is to furnish energy and maintain heat. They contain carbon, hydrogen, and oxygen, and include foods containing starch and sugar. Examples: vegetables, fruits, cereals, sugars, and gums.

The chief office of fats and oils is to store energy and heat to be used as needed, and constitute the adipose tissues of the body. Examples: butter, cream, fat of meat, fish, cereals, nuts, and the berry of the olive-tree.

The chief office of mineral matter is to furnish the necessary salts which are found in all animal and vegetable foods. Examples: sodium chloride (common salt); carbonates, sulphates and phosphates of sodium, potassium, and magnesium; besides calcium phosphates and iron.

Water constitutes about two-thirds the weight of the body, and is in all tissues and fluids; therefore its abundant use is necessary. One of the greatest errors in diet is neglect to take enough water; while it is found in all animal and vegetable food, the amount is insufficient.

CORRECT PROPORTIONS OF FOOD

Age, sex, occupation, climate, and season must determine the diet of a person in normal condition.

Liquid food (milk or milk in preparation with the various prepared foods on the market) should constitute the diet of a child for the first eighteen months. After the teeth appear, by which time ferments have been developed for the digestion of starchy foods, entire wheat bread, baked potatoes, cereals, meat broths, and occasionally boiled eggs may be given. If mothers would use Dr. Johnson's Educators in place of the various sweet crackers, children would be as