EXAMINATION OF FROZEN EGG PRODUCTS. 17 
10. A comparison of the average results for acidity of fat of 1.49 
and 1.72 cc. of N/20 sodium ethylate required per gram, respectively, 
in whole egg (Table 1) and in yolk (Table 3), both prepared from the 
freshest eggs obtainable, shows that higher figures were obtained in 
the case of yolk. Theoretically, the figures should be identical, or 
very nearly so. It is possible that this difference is due to the 
removal of substances from the white of the egg by the solvent or by 
the presence during drying of a relatively large amount of protein in 
the whole egg. For a tabular summary of this discussion see Tabie 
26 (page 76). 
PROGRESS OF THE INVESTIGATION. 
PREPARATION OF SAMPLES. 
Karly in August, 1917, under the supervision of two representatives 
of the Bureau of Chemistry who have had wide experience in grading 
eges both before the candle and while out of the shell, the frozen egg 
samples were prepared in four commercial houses which are as wel] 
equipped as the average breaking plant. In candling and grading 
the eggs and in preparing the samples representatives of the manu- 
facturers were always present. The manufacturers showed a most 
eratifying spirit of cooperation throughcut the entire investigation. 
During the preparation of the samples careful records were made of 
all the available informaticn concerning the past history of the 
breaking stock and its distribution. As far as possible records were 
also kept of the number and kinds of eggs which entered each sample. 
In the case of the samples designated as commercial in Tables 8 to 23 
the manufacturers were allowed to follow their own grading, of which 
the Bureau representatives kept a careful record. In the samples 
designated as experimental the grading was done by the Bureau of 
Chemistry representatives. 
The Department of Agriculture has taken the position that only 
two grades of frozen egg material should be prepared—namely, food 
ege and tanners’ egg.t Several manufacturers, however, prepare 
more than one grade of food product. For this reason experimental 
samples presumably of more than one grade were prepared, but this 
fact is not to be considered as indicating the approval of the Bureau 
of Chemistry of such a procedure commercially. In a number of 
cases as nearly as possible identical types of samples were prepared 
in several different houses with different raw materials, different 
equipment, and different breakers. _ 
1U. 8. Dept. Agr. Bul. 224, p. 21. 
158352°—20—Bull. 846——_2 
