PURE AND IMPURE FOODS. 



" What a Man Eats He Is." 

 Edited by C. F. Langworthy, Ph.D. 

 Author of ' On Citrac^nic, itaconic and Mesaconic Acids, '"'Fish as Food,'' etc. 



USES OF EGGS. 



The ways in which eggs are served 

 alone or in combination with other food 

 materials are numerous. Cooked in va- 

 rious ways they are a favorite animal 

 food, taking the place of meat to a certain 

 extent ; while raw eggs, usually seasoned, 

 are by no means infrequently eaten. 

 Boiled eggs are often used for gar- 

 nishing or ornamenting different foods. 

 Eggs are combined with other materials in 

 various ways in many made dishes. They 

 are used in making cakes and such foods 

 to improve their flavor, color, and texture; 

 while in custards, creams, etc., they thicken 

 the material and give it the desired con- 

 sistency. The white of the egg is also em- 

 ployed in making icings and confectionery. 

 Well beaten or whipped egg white is used 

 to leaven many forms of cakes and similar 

 foods, as well as to improve the flavor. 

 The beaten white encloses air in small bub- 

 bles, which become distributed throughout 

 the: mass of dough in mixing. The heat of 

 cooking expands the air and makes the 

 walls of the air bubbles firm, so that the 

 porous structure is retained. The power 

 to inclose and retain air varies, being 

 greatest in the fresh egg and much less- 

 ened in packed or old eggs. Convenient 

 leavening powders have lessened the num- 

 ber of eggs used for this purpose. Sponge 

 cake, however, is a familiar example of 

 food so leavened. This use of eggs ex- 

 plains some of the recipes in old cookery 

 books which call for such large numbers of 

 eggs. These uses are all familiar ; the rea- 

 sons for them are doubtless seldom 

 thought of. 



There are several simple ways of cook- 

 ing eggs which are commonly fol- 

 lowed. Thus, the egg in the shell is 

 cooked by immersion in hot or boiling wa- 

 ter, or is less commonly roasted. After 

 removal from the shell, the egg is cooked 

 in hot water or in hot fat. In the latter 

 case it may or may not be beaten or stirred. 

 Combined with other materials to form va- 

 rious made dishes, eggs are boiled, baked, 

 steamed, or fried as the case may be. The 

 total number of ways of serving and pre- 

 paring eggs is large, but in nearly every 

 case it will be found that the method of 

 preparation is only a more or less elab- 

 rate modification of one of the simple 

 methods of cooking. 



Numerous experiments have been made 

 to show the changes which actually take 

 place when egg albumen is heated. If the 



egg white is gently warmed, no change is 

 noticed until the temperature reaches 134 

 degrees Fahrenheit, when coagulation be- 

 gins. White fibers appear, which become 

 more numerous, until at about 160 degrees 

 Fahrenheit the whole mass is coagulated, 

 the white almost opaque, yet tender and 

 jellylike. If the temperature is raised 

 and continued to 212 degrees Fahrenheit 

 the temperature of boiling water, the 

 coagulated albumen becomes much harder, 

 and eventually more or less tough and 

 hornlike. It also undergoes a shrinkage. 

 When the whole egg is cooked in boiling 

 water, the temperature of the interior does 

 not immediately reach 212 degrees Fahren- 

 heit, several minutes being probably re- 

 quired. It has been found by experiment 

 that the yolk of egg coagulates firmly at a 

 lower temperature than the white. 



The foods in which eggs are combined 

 with other materials range from a simple 

 custard or cake to the most elaborate of the 

 confectioner's products. In all such dishes 

 as previously noted, eggs are used to give 

 consistency, color, flavor or lightness. 



Eggs are especially rich in protein, the 

 nitrogenous ingredient of food. This ma- 

 terial is required by man to build and re- 

 pair the tissues of the body. Some energy 

 is, also furnished by protein, but fats and 

 carbohydrates supply the greater part of 

 the total amount needed. Combining eggs 

 with flour and sugar (carbohydrates) and 

 butter, cream, etc. (fat), is perhaps an un- 

 conscious effort to prepare a food which 

 shall more nearly meet the requirements of 

 the body than either ingredient alone. 

 When eggs, meat, fish, cheese or other 

 similar food rich in protein are eaten, such 

 other foods as bread, butter, potatoes, etc., 

 are usually served at the same time, the 

 object being, even if the fact is not real- 

 ized, to combine the different classes of nu- 

 trients into a suitable diet. The wisdom 

 of such combination, as well as of other 

 generally accepted food habits, was proved 

 long ago by practical experience. The rea- 

 son has been more slowly learned. 



As previously stated, the egg white, 

 when heated at the temperature of boiling 

 water for a considerable time, becomes 

 hard and contracts. This explains the 

 curdling of custards, shrinkage and tough- 

 ening of omelets, souffles, meringues, 

 sponge cake and similar mixtures. The 

 firm coagulation of albumen at 212 degrees 

 Fahrenheit explains the use of egg white 

 for clarifying coffee, soup, or other liquids. 



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