UNITED STATES DEPARTMENT OF AGRICULTURE 
| BULLETIN No. 391 $jij| 
\rZ Contribution from the Bureau of Chemistry <Slk*s£^M?? 
Contribution from the Bureau of Chemistry 
CARL L. ALSBERG, Chief 
Washington, D. C. 
PROFESSIONAL PAPER 
December 10, 1918 
ACCURACY IN COMMERCIAL GRADING OF 
OPENED EGGS. 
By M. K. Jenkins, Assistant Bacteriologist, and Norman Hendrickson, Assistant 
Chemist, Food Research Laboratory. 
CONTENTS. 
Introduction 
Purpose, plan, and extent of investigation. . . 
History and bacterial content of samples 
Effect of condition of shell on bacterial con- 
tent of egg 
Relation between number of bacteria and 
physical condition of the egg contents 
Page. 
Descriptions and bacterial counts of eggs 
graded out of the shell 14 
Effect of contaminated eggs upon composite 
products 18 
Eggs rejected during grading 21 
S ummary 25 
INTRODUCTION. 
The quality of liquid egg used in making frozen or dried egg 
products depends upon two factors : First, the character of the eggs 
entering the product; and, second, the cleanliness of preparation. 
Eggs, good and bad, as they appear before the candle and out of the 
shell, with their respective chemical and bacterial characteristics, 
have been discussed in Bulletin 51. 1 The precautions necessary to 
insure cleanliness when opening the eggs and collecting their con- 
tents to be frozen or dried have been discussed in Bulletin 224, 2 in 
which publication much attention is directed also to the character 
of the eggs used. During the progress of the work the question of 
the accuracy of grading eggs by sight, smell, and taste frequently 
arose. It was observed that samples made from comparatively 
high-grade stock sometimes had a higher bacterial content than 
could be accounted for on the basis of faulty manipulation. They 
seldom showed chemical evidence of decomposition. It was ob- 
i A Bacteriological and Chemical Study of Commercial Eggs in the Producing Districts of the Central 
West. U. S. Dept. Agr. Bui. 51, 77 p., 8 pi., 2 fig., July 20, 1914. 
2 A Study of the Preparation of Frozen and Dried Eggs in the Producing Section. U. S. Dept. Agr. 
Bui. 224, 99 p., 17 pi., 7 fig., Apr. 28, 1916. 
62492°— Bull. 391- 
