Eggs contain all the ingredients necessary to support life and develop the organism.
From their chemical composition it is readily understood how they are such valuable articles of food in the dietetic treatment of disease, especially in some ailments occurring in childhood and youth.
Comparing the composition of the edible part of the whole egg with that of moderately lean meat, we find as follows: -
Protein .. . .
The nutritive matter is thus seen to be almost the same as meat, eggs being poorer in protein but much richer in fat. The nutriment found in the yolk and white of the egg is as follows: -
Water . . .
Protein . . ,
The white of egg contains its protein in a solution enclosed in numberless little cells. When white of egg is beaten up, the walls of the cells are ruptured and the protein is set free. The result of beating is to increase the digestibility of egg-white, the protein being more easily broken up when released from the cell.
From this table it is evident that the yolk of the egg is much the most nourishing portion. In its ash there are some very important mineral constituents, viz., phosphoric acid, lime, and iron. The phosphorus and iron are almost entirely present as organic compounds. As mineral matters are must easily absorbed when combined with an organic substance, it follows that yolk of egg is a useful adjunct in the treatment of several forms of nutritional and blood diseases. In chlorosis and some other forms of anemia, and also in rickets, the great richness of the yolk in lime, phosphorus, and iron make it most valuable.
The fats present are the same as those present in butter. They appear in emulsion form, and are thus very easily digested. Eggs, from their chemical composition, should be used with a carbohydrate diet. The usual custom of preparing rice and starchy preparations, such as arrowroot, tapioca, cornflour, with eggs in the making of milk puddings is a perfectly right one, the result being a perfect food. The nutrient value of an egg corresponds approximately to a full half-tumblerful of milk, or to 1 1/2 ounces of fairly fat meat.
The digestibility of eggs varies, depending on the form in which they are taken. From results of experiments by Penzoldt, it is surprising to find that a raw egg takes longer to leave the stomach than a lightly boiled one; a raw egg is hardly digested by the stomach, being passed into the duodenum almost unchanged. A raw egg, therefore, is probably the better article of diet for a stomach requiring rest. Hard-boiled eggs are much more indigestible than those lightly boiled.
Eggs are very constipating for some people This is partly due to the large amount of lime present, and partly to the fact that absorption in the intestine goes on to such an extent that only a very small residue remains.
Some patients show a remarkable idiosyncrasy to eggs, being unable to take any without acute symptoms of gastrointestinal derangement supervening. Others are unable to take eggs in a plain form, but can take them in the form of a pudding or cake. If the absorption of eggs from the intestine is delayed, decomposition ensues, with production of sulphuretted hydrogen and ammonia with accompanying intestinal derangement.
Ovo, a powder made up in packets, is sold as a substitute for eggs; each packet containing the equivalent of one egg. It is the egg dried, and on the application of water is redissolved. Its only use is for cooking purposes if fresh eggs are not obtainable.
Egg and custard powders are also sold as substitutes for eggs. These have no nutritive value, and are in no way equal to genuine custard. They consist chiefly of starch, a little baking soda, tartaric acid, and some vegetable dye to give the yellow colour.
Raw Eggs are of special value in the treatment of tuberculosis. They are given in the following ways: -
Take the white of an egg, and to this add twice its own volume of water and strain it through muslin. This gives about 3 ounces of a clear solution, containing as much protein as is found in an average sample of commercial beef juice.
This fluid added to a beef extract - either home-made beef-tea or to one of the many beef extracts in the market (lemco, etc.), just dissolved in hot water - makes a very nutritive solution almost indistinguishable from beef juice, and at a fraction of the cost. Egg-white water added to any of the beverages (see p. 275) makes them at once possess a decided nutritive value, and is useful especially in pyrexial conditions.
1 fresh egg.
1 tablespoonful of vinegar.
Put the vinegar into a small cup and break the egg into it. Serve at once This is a very digestible way of serving an egg, and it is very cool and refreshing.
The next three recipes give the way of making up raw eggs into nourishing stimulant drinks. By adding nutmeg, cinnamon, or lemon juice, the flavour can be altered.
1 teacup of milk.
1 teaspoonful sugar.
Beat up the egg, add to it the wine and sugar, beat together with a fork slightly, and strain through a fine wire strainer. Heat the milk in a small saucepan, and when almost boiling pour it on to the egg, stirring all the time. Serve hot.
This can be made without wine, flavouring with cinnamon or lemon juice. The yolk of the egg only may be used, and soda-water instead of milk.
1 cup of milk.
1 teaspoonful sugar.
1 white of egg.
Boil the milk or mike it thoroughly hot; beat up the white of egg to a stiff froth. Pour the boiling milk over the white of egg, stirring all the time. Add sugar to table, and serve.
1 white of egg.
1 tablespoonful cream.
I tablespoonful brandy Sugar to taste.
! up the white of egg stiffly. Add to it the brandy and cream. with a little sugar if wished. Mix very thoroughly, and serve.
1 white of egg.
1 tablespoonful cream.
1 tablespoonful brandy.
Beat up the white of egg stiffly. Add to it the brandy, cream, and a little sugar. Mix very thoroughly, and serve.
Beat up an egg; add a glass of sherry and halt a pint of gruel; flavour with lemon peel, nutmeg, or sugar.
Cooked Eggs appear as the main basis in custards, souffles, and omelets. They are also used with carbohydrates in the making of puddings, and for the thickening of soups and sauces. Eggs cooked by themselves can be used in the following ways: -
Put enough water into a small saucepan to entirely cover the egg. Allow the water to boil; lower the egg gently into it. Draw the pan to the side of the fire, and allow the water to simmer slowly. Cook the egg for three and a half to four minutes, then lift out and serve at once. If it is allowed to stand it becomes hard.
1 egg. Boiling water.
Lemon juice. Pinch of sak.
Round of toast.
Break the egg into a cup, keeping the yolk whole. Into a small saucepan of boiling water add a pinch of salt and a squeeze of lemon juice. Draw the water to the side, and when just off the boil slip the egg carefully into it. Cook slowly for three minutes, when the white should be quite set. Lift it out with a small fish-slice or perforated spoon, and trim off any ragged edges of white. Place on a square of newly-made toast, and serve at once.
If required, this egg can be made richer by being served on buttered toast, or a little hot cream poured over it. A poached egg served on 2 tablespoonfuls of carefully prepared spinach is also a very nice dish.
I tablespoonful milk.
Pepper and salt. 1/4 ounce butter.
A piece of toast.
Heat in a small saucepan the milk. Pour into the hot milk the egg beaten up in a cup with pepper and salt. Stir quickly over the fire until it begins to thicken, remove it then from the fire and continue stirring until it forms a creamy mixture. Put on a piece of newly-made toast, and serve at once. If cooked too long, or allowed to stand, it becomes leathery and indigestible.
Grease a china or paper ramekin case thoroughly; into this carefully break an egg. Add pepper and salt and a teaspoonful of cream. Place in a moderate oven and bake three or four minutes until lightly set, and serve at once.
Add the yolk of two eggs and a cupful of beef-tea, with pepper and salt to taste; butter a cup or jam-pot, pour the mixture into it, let it stand in a pan of boiling water till the custard is set.