The Worcester domestic science school's one year course laboratory cook book

The nitrogenous foods constitute the fundamental principle of cell life; they contain nitrogen and yield nitrates, nitrites and ammonia when decomposed outside the body by certain bacteria; hence their name nitrogenous. One of the purest forms of nitrogenous food is the white of egg; other examples are fish, cheese, most of solid part of eggs, lean meat of all kinds; lobster, mushrooms and gluten of wheat. Proteid or nitrogenous food should be cooked by gentle heat as firmly coagulated proteid is a wholly different substance chemically than the delicately coagulated. When cooked hard and dry it is much more difficult of digestion. After meats are seared to retain juices they should then be cooked by a lower heat. The proteid foods are found most abundant in the animal world. The carbonaceous foods consist largely of carbon and water and are among the most rapidly formed in the vegetable kingdom. The starches and sugars are the principal types of this class. Potato, rice, tapioca, full grown peas and beans, bananas — vegetables and fruits. Combined with the starch and sugar we find the organic acids and salts. The sugar, salts and acids arc easily lost or destroyed in preparing and cooking these foods. Vegetables and fruits should not be soaked in water. Wash with brush, do not scrape, cook quickly, covered and reabsorb as much of water as possible. Baking is a more economical process. Thrust into boiling water to cook. Leave cover off in cooking vegetables rich in sulphur compounds; as beans, cabbage, cauliflower, brussel sprouts, onions. Wash spinach in seven waters without soaking and cook covered in water that adheres to leaves. Cellulose and starchy part of turnips may be converted to dextrine by cooking by baking process. In this way valuable salts are preserved. Cellulose of onions may be converted to sugar by baking process and starch of bananas to dextrine and sugar by same process. Steaming also is better than boiling. If the nutrients be lost in preparing vegetables and fruits, cellulose, a liber, is about all that is left. It is not a nutrient. Celery, spinach, asparagus, tomatoes, lettuce, riee are rich in organic mineral matter. Do not waste it. The human body needs it. The glycerides are the fats and oils of all foods. They consist of fatty acids and glycerine combined chemically. They should be kept cool and covered tightly. Fats exposed to the air are acted upon chemically by the oxygen of the air and the fatty acid is thus set free. This is the first step on the road to rancidity which renders fat unfit for household use. All kinds of fats and oils contain acids. Cream is the most easily digested of fats and olive oil ranks next. Olive oil contains hydrochloric acid free, which is a natural antiseptic. Fats require more oxygen for their combustion than starches and thus yield more heat. They should be eaten more freely in winter than any other season. Fats and oils are found abundant in the animal kingdom. Egg yolk contains considerable fat, and oysters a little. In the vegetable world nuts yield the most while carrots and parsnips contain some and beans and potatoes only a trace. The volatile oils are easily lost by the boiling process. The organic acids are found in all foods and by uniting with bases form compounds that render the blood and lymph alkaline in health. Preserve the acids.