l88 BACTERIOLOGICAL METHODS 



increase in proportion to the time of storage, until a maximum 

 development is reached. The bacterial flora of the white and 

 of the yolk of the egg differs quantitatively as well as qualita- 

 tively. It may happen that the yolk is badly infected while 

 the white is in comparatively good condition. As a rule, how- 

 ever, if the yolk is highly contaminated the white is similarly 

 affected. In fact the first decomposition changes generally take 

 place in the periphery of the egg albumen, the infection taking 

 place via the exterior of the shell. 



Commercially, eggs are designated as fresh, stale, storage; 

 firsts, seconds and thirds (when sorted as to size); watery and 

 weak when the white is thin; heat eggs; leakers, checks and 

 mashed when the shell is more or less broken; eggy, strong, 

 musty, sour and stale as to odor; blood ring, sour rot, white rot, 

 light rot, spot rots, moldy, black rots, etc., when more or less 

 rotted and decomposed; green or grass eggs when the white is 

 more or less green colored through the invasion of bacteria. 

 These terms have no scientific importance and are of no signifi- 

 cance to the food bacteriologist, beyond that of indicating the 

 probable or likely condition and contamination and probable 

 cause of the change or deterioration of the eggs so designated. 



The old-time popular methods of testing eggs by candling, 

 by shaking to determine "looseness," floating on brine, noting 

 discoloration of the shell, and by the odor, have their value in 

 practice but are far from reliable. An egg which gives off the 

 odor of sulphuretted hydrogen is universally recognized as bad, 

 rotten or spoiled. In Germany eggs are pronounced spoiled if the 

 white is gelatinous in consistency (as in old eggs from which 

 moisture has escaped) or yellowish in color (also due to age), 

 or if the yolk is more or less adherent to the shell or is more or 

 less mixed with the white. A fresh egg broken in the manner 

 customary in the kitchen allows the entire contents, yolk and 

 all, to fall out into a receptacle without rupturing the yolk. 

 The white should be of uniform consistency, uniformly trans- 



