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PREPARATION OF FROZEN AND DRIED EGGS. 15 
COMPARATIVE STUDY IN TWO HOUSES ON EGGS BEFORE AND AFTER 
DESICCATION. 
The belt system used in E and F houses differed in some respects. In E house the 
hot air entered the ducts in which the belts circulated through several flues and was 
expelled through two others. In F house there was one inlet and one outlet for the 
hot air. By the arrangement of the air ducts in E house the supply of air coming in 
contact with the drying egg was replenished before it had become saturated with 
moisture. The temperature of the intake air in E house varied from 135° F. to 160° F. 
for whole egg, and in F house it was 160° F. for yolk and 140° F. for mixed egg. The 
temperature of the outgoing air was about 10° lower in E house and about 30° lower 
in F house than the incomingair. E house desiccated about 150 pounds of whole egg in 
one hour and F house about 80 pounds. 
The belts of E house were considerably longer than those of F house; consequently 
they were supported on the lower side by rollers. The portion of the egg on the belt 
coming in contact with these rollers did not dry as quickly as the films of eggs on 
the exposed sections of the belt. As a result, sticky masses, commercially termed 
‘‘wet lumps,’’ were mixed with the flaky egg scraped from the belts. The imper- 
fectly dried portions, however, represented but a small amount of the final product. 
They were screened and subjected to further drying. The average moisture content 
of the dried product immediately after being removed from the belts was at E house 
8.82 for the whole egg. E house did not subject the dried egg to secondary drying. 
F house, however, exposed the product to a temperature of 100° F. for about five 
hours. The percentage of moisture then averaged 6.13 for the mixed egg and 5.04 
for the yolks, as against 11.24 per cent for mixed egg and 11.21 per cent for yolk when 
the dried egg was removed from the belts. 
BACTERIAL CONTENT. 
Eighteen comparative examinations were made of the product in E house before 
and after desiccation. The results given in Table E-V (Appendix, p. 74) show in 
practically every case (if the count of the dried product be divided by 3 to make it 
comparable with the liquid egg) that there is a reduction in the number of bacteria 
during the process of desiccation. 
The lowest count found in samples of the flaky dried egg, as shown in Table E-IIT 
(Appendix, p. 70), was 65,000 per gram and the highest 20,000,000. The average 
count for the 48 samples was 3,600,000. The number of B. coli varied from 0 to 
1,000,000 per gram. Only 6, or 12.5 per cent, contained 1,000,000. (Table E-VIII, 
Appendix, p. 78.) 
The bacterial content of the samples of ‘‘ wet lumps’’ averaged 6,900,000 and varied 
from 1,100,000 to 18,000,000 per gram. Corresponding samples of flaky egg contained 
between 430,600 and 12,600,000 organisms per gram (Table E-II). Comparative results, 
given in Table E-I! (Appendix, p. 68), indicate that in some instances there is a 
multiplication of organisms in wet lumps during the process of desiccation. There 
was practically no difference in the’ bacterial content of wet lumps before and after 
secondary drying. 
In the spring of the year there was practically no increase in the number of bac- 
teria during drying. In thesummer, however, there was appreciable multiplication 
during desiccation (see Table F-I, Appendix, p. 80). This is undoubtedly due to 
the warmer weather and the greater amount of water in the air during the summer. 
It is probable that an increase in the air supply to the belts and an increase and 
rearrangement of the inlet and outlet ducts would facilitate desiccation and prevent 
multiplication of bacteria without diminishing the solubility of the dried product. 
AMMONIACAL NITROGEN. 
The amount of ammoniacal nitrogen found in the Alesiccated products of E and F 
houses is not comparable with the amount present in liquid egg before drying. For 
example, the parallel tests given in Table E-V (Appendix, p. 74) showed that the 
percentage of ammoniacal nitrogen calculated on the dry basis varied from 0.0073 to 
0.0093 in the liquid egg and from 0.0009 to 0.0016 in the corresponding product after 
desiccation. Similar variations can be seen in Table F-VI (Appendix, p. 76). These 
results indicate that a portion of the ammoniacal nitrogen was volatilized during 
desiccation. 
_ The amount of ammoniacal nitrogen volatilized from the product during desiccation 
1s not constant, according to the above tables. For instance, samples 41079 and 41085 
listed in Table E-V contained 0.0093 per cent of loosely bound nitrogen in the liquid 
form, but after desiccation one contained 0.0009 per cent and the other 0.0015 per cent. 
Since, therefore, the amount of loosely bound nitrogen lost from eggs during drying is 
