268 THE PRESERVATION OF FOOD PRODUCTS 
completely. Even after the shell is deposited and the egg laid, 
bacteria are capable of entering it. The shell is somewhat porous 
and it has been proved by experiment that bacteria can pass 
through the pores. In short, the egg must be looked upon as a 
highly nutritious food product, in most cases already inoculated 
with bacteria, and a body which is practically sure to undergo 
decay in the course of time. There are fewer bacteria in winter 
eggs than in those laid in summer, and the cleaner the nest the 
less the bacterial contamination. 
It is, however, possible, by certain devices, to delay or prevent 
the growth of bacteria in the egg. The bacteria found in eggs 
do not develop at low temperatures and the eggs may be kept 
almost indefinitely at a temperature of 34°. But since cold 
storage is not always available, other methods must usually be 
adopted. One of the simplest and best is by the use of water 
glass, a material made of sodium and potassium silicate. This 
may be purchased cheaply in the form of a thick syrup. It is 
then mixed with nine parts of water and placed in clean stone 
jars. The eggs are placed in the mixtures and the whole set aside 
in a cool place. If the temperature is not allowed to rise above 
6o° the eggs may be kept from decay for a long time by this 
method, many weeks and even months elapsing before they will 
decay. In preserving eggs in this way it 1s important to know 
that April eggs will keep better than May eggs and these better 
than June eggs, while eggs laid in the hot months of the summer 
are less easily preserved, a fact probably due to a greater bacterial 
contamination during the warmer months. From this it will 
follow that the June storage eggs should be used first and the 
April preserved eggs last. 
Eggs thus preserved will keep from decay, but they will lose 
their fresh taste. Indeed, this fresh flavor disappears in a very 
few days and there is no way known by which it can be retained 
for very long. But after the fresh taste is gone the eggs will 
remain without further change for a long time and be usable. 
