60 BULLETIN 51, U. S. DEPAETMENT OF AGRICULTURE. 



The samples given in Part 1 of Table 2G were opened aseptically. 

 The organisms found are, therefore, referable strictly to the egg. 

 The other samples were obtained in packing houses and were opened 

 into sterile cups. It is possible that a few extraneous organisms 

 may, therefore, be included in these bacterial counts, but the error 

 is small. There is a close agi'eement between maximum and mini- 

 mum counts in the samples obtained by the two methods. While but 

 31 individual commercial samples were examined, many of them rep- 

 resent a large number of eggs and a few approximate 5 pounds each. 

 Twenty-six of the 31 samples, or 83.9 per cent, show counts of over 

 10,000,000 per gram. 



The predominating organism has been found to be Pseudomonas 

 syncyanea {Jllgida)'^ and the color of the egg white is due to the 

 ability of this form to produce a diffuse, green fluorescence in the 

 medium in which it grows. When pure cultures of this pseudo- 

 monas were injected into a fresh egg the white assumed the char- 

 acteristic color in a few days and later developed a fetid odor. 



The pseudomonas is not, however, in pure culture when occurring 

 in eggs with a green white. B. coli, as well as other organisms, are 

 generally found with it. The numbers of B. coU, as determined by 

 lactose bile fermentation, varied from 10 to 1,000,000 per gram. 



The eggs which were physically in good' condition and odorless, 

 and some of which were separated into white and yolk, are listed 

 in Table 26, Part III. Others, having an odor but not sufficient to 

 preclude use according to old methods of gTading, are given in 

 Part IV. It will be observed that the white of the egg has a much 

 greater number of organisms than the yolk, though the infection 

 in the latter is also extensive. A further indication of a mixed in- 

 fection is the fact that organisms which liquefy gelatin are com- 

 monly present in numbers. The pseudomonas isolated does not 

 liquefy gelatin. It does not grow to any extent at 37° C. ; yet the 

 counts at this temperature are frequently decidedly higher than the 

 sum of the number of liquefiers and the organisms developing in lac- 

 tose bile with gas production. Apparently, therefore, these eggs Avith 

 green-colored whites are recognized by the characteristic color pro- 

 duced by one species, though they are the harbingers of a number 

 of species as well as of great numbers of organisms. 



This argument is reenforced by the amount of loosely bound 

 nitrogen found. When the egg is not separable into white and yolk 

 the amount of nitrogen is uniformly high — much higher than in 

 eggs commonly used for food. Wlien the degeneration of the egg 

 is not sufficient to interfere Avith its physical integrity the amount 

 of loosely bound nitrogen is not materially increased. It might 



1 This organism was identified by Evelyn Witmer, of the staff of the Food Research. 

 Laboratory. 



