14 BULLETIN 471, U. S. DEPARTMENT OF AGRICULTURE. 
various made dishes, eggs are boiled, baked, steamed, or fried, as the 
case may be. 
Changes in weight are often noted when foods are prepared for the 
table. These vary with the kind of material and the method of prepa- 
ration, but, in general, loss in weight is due to volatilization, and gain 
to the absorption of water. Much careful experimenting with eggs 
cooked in the shell shows that if the egg remains in water a few min- 
utes it loses only a very little material, probably water, which passes 
out through the porous shell. If it is left in the water for a longer 
time it may gain weight by absorbing water. In either case the 
change is too small to modify the food value of the egg appreciably. 
Different methods of cooking cause marked changes in the appear- 
ance and structure of eggs. Thus, boiled eggs — that is, eggs cooked 
in the shell in hot, though not necessarily boiling, water — vary greatly 
in hardness, according to the length of time the cooking is continued, 
the method of procedure, etc. The directions commonly given for 
preparing soft-cooked, medium-cooked, and hard-cooked eggs vary. 
An} 7 of them without doubt will give the desired result if sufficient 
care is exercised. The chief difficult} 7 is in securing uniform results, 
especially with soft-cooked or medium-cooked eggs. It must be re- 
membered that such results can not be expected when conditions vary. 
The time of cooking, the quantity of water used, the number, size, 
freshness, and temperature of the eggs, and the kind of vessel used 
are important factors. Thus, eggs which have been kept in an ice 
chest require more heat to warm them before cooking begins than do 
those which have been kept at room temperature. Again, so appar- 
ently trivial a detail as the sort of vessel used (whether earthen or 
metal ) , or the place where the vessel stands during cooking, may pro- 
duce different results. Even after the eggs are taken out of the water 
they may continue to cook, and the length of time they stand before 
using may make a noticeable difference in their consistency. Many 
persons prefer to have eggs cooked at the table in a chafing dish or 
other suitable vessel. In such cases the conditions may be controlled 
with comparative ease, and uniform results obtained with a little 
practice and care. 
As previously stated, egg white, when heated at the temperature of 
boiling water for a considerable time, becomes hard and contracts. 
This explains the curdling of custards and the shrinkage and tough- 
ening of omelets, souffles, meringues, sponge cake, and similar mix- 
tures. The firm coagulation of albumin at 212° F. explains the use of 
egg white for clarifying coffee, soup, or other liquids. The albumin, 
which is mixed with the liquid before boiling, coagulates and incloses 
the floating particles, leaving the liquid clear. When eggs are re- 
moved from the shell, a little of the white usually clings to the inner 
surface unless it is scraped. Such eggshells are often used for clarify- 
