FoodNet

A text-book of cooking

1915

Page 149

Presented as published in 1915. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
Too much or too little protein is often harmful and pro- duces serious results. Beside other harmful effects, too much protein may cause intestinal disturbances, an excess of acid in the body, and an overtaxing of the excretory organs. On the other hand, the use of too little protein may produce imperfect nourishment. Concerning the quantity of protein used in diet, there has been much difference of opinion. Atwater, an American authority, thought that there should be a generous supply, i.e. a surplus of protein, to supply the demands of body building. Chittenden, another American authority, believes in just enough protein to meet the de- mands of the body. However, the use of sufficient protein food to produce from ten to fifteen per cent of the total Calories has been found both practical and satisfactory. Nutritive Ratio. — The ratio of the fuel value of protein or nitrogenous food to the fuel value of fat and carbohydrates or non-nitrogenous food is termed nutritive ratio. In formulat- ing diets, it is helpful to have the nutritive ratio given with the total energy requirement. Expressing ratio in the form of a fraction and using 1 as the numerator, the above protein requirement may be expressed as : ^ to -£-= nutritive ratio, i.e. for every Calorie produced by protein nine to five and seven tenths Calories should be produced by fat and carbohydrates. Daily Carbohydrate and Fat Requirement. — Although pro- tein may furnish the body with energy, its more important function is to build the body. If carbohydrates and fat are present with protein, the former supply energy and allow the protein to perform its more important function of build- ing the body. For this reason, carbohydrates and fat are 372 THE PLANNING AND SERVING OF MEALS termed proteiyi-sparing food. There should always be enough carbohydrates and fat to furnish energy to the body, so that the protein can be used exclusively for body build- ing. In the growing period of youth or after a wasting disease, it might seem that u flesh " could be " put on " by increasing the quantity of body-building food. But such is not the case. The most effective work in building the body can be accomplished by using a normal amount of protein and a generous supply of ash, carbohydrates, and fat. With such a combination, the protein can be used exclusively for body-building. For practical purposes, the following general statement concerning the carbohydrates and fat requirement is believed to be adequate : If the total Calories and the number of Calories yielded by protein meet the requirement of a dietary standard and the food composing the diet is varied in composition, the carbohydrates and fat will exist in satisfactory proportion. Daily Ash Requirement. — Since ash is not a combustible foodstuff, it cannot be included in the foodstuffs whose energy requirement can be measured. Although ash exists in small quantity in food, the use of certain ash con- stituents is considered as necessary as the use of protein. A diet may meet the total energy, the protein, the carbohy- drate, and the fat requirements, yet may be lacking in certain essential mineral materials. It is especially necessary to include food containing phosphorus, iron, and calcium in one's diet. Fruits, green vegetables, whole grains, milk, and eggs are common foods which should be used generally. (See lists of foods containing ash, pp. 322 and 323.) QUESTIONS Compute (from the table on p. 368) the energy requirement of at least two members of your family. Compute your own energy re- quirement from this table. Compare it with the table on p. 369. Compute the nutritive ratio of the energy requirements calculated above. CHAPTER IX Measurement op the Fuel Value op Food applied to Daily Food Requirement