EFFICIElsrCY OF COMMERCIAL EGG CANDLING. 3 



from each lot were transferred to a commercial cold-storage ware- 

 house, and withdrawn for candling between the early part of Novem- 

 ber and the latter part of March. The eggs used for these experiments 

 varied in quality from spring jSrsts and dirty eggs to summer jfirsts, 

 seconds, and dirty eggs. These eggs were candled by skilled opera- 

 tors in two large concentrating centers in the East. The storage- 

 packed eggs were, therefore, a very fair representation of the various 

 grades of fresh-gathered market eggs.^ The accuracy of the candling 

 of the breaking stock was observed in several plants in the Middle 

 West and in two in the East. The candling crews varied widely in 

 efficiency. The rejected eggs studied were from both experienced 

 and inexperienced candlers. 



RELATION OF QUALITY OF EGGS TO ACCURACY IN CANDLING. 



An anah^sis of the bad eggs found in eggs candled as edible showed 

 the presence of two distinct groups — one consisting of eggs which are 

 commonly recognized by candling, and the other of types which can 

 be detected only out of the shell. The proportion of the first group 

 in eggs candled as edible may, therefore, be used as an index to the 

 accuracy of candling. The ideal to be attained in candling is the 

 elimination of all errors in the grading of those types of eggs which 

 can be identified before the candle. 



The accuracy of skilled candlers depends upon the quality and 

 condition of the stock. Generally speaking, the more bad eggs there 

 are present, the greater will be the number missed. This is 

 not always the case, however, because the type of deterioration in- 

 fluences the accuracy of candling. For example, the black and 

 white rots, moldy eggs, and heavily stuck yolks, characteristic of 

 the bad eggs occurring in dirty eggs, are much more readily detected 

 by candling than the light-blood rings, slightly stuck yolks, and 

 partially disintegrated yolks, common in summer stock (Tables 1 

 and 11). 



1 In this publication the terms " fresh-gathered " and " fresh-marlseted " eggs refer to 

 eggs which are marl^eted without the intervention of cold storage. 



