REPORT OF THE BACTERIOLOGIST XIX 
save much time but also afford the preparation of a higher 
grade of culture media than can be obtained by other 
sources of heat much more expensive. 
Studies and compilations are in progress on the subject 
of pasteurized milk as affecting its food value. Experts 
who know the most about pasteurized milk are nearly unan- 
imous in the belief that the process is detrimental rather 
than beneficial. It is demonstrated that the food value is 
diminished by the process, and further, products seem to be 
formed which are unfavorable in the process of digestion, 
especially for young children and infants. 
Preliminary preparations are in progress for a study of 
anaerobic bacteria in milk products. This class of organ- 
isms grows without the presence of oxygen from the air. 
Conditions favorable for them occur in the deeper layers of. 
milk, ripening cream, and interior of cheese. There are cer- 
tain phenomena which occur in milk products which are 
puzzling without the activity of some such organisms. 
Partial reports will be prepared on those lines sufficiently 
advanced to admit and placed in this volume. The other 
lines of investigations will be continued and reported when 
more complete. 3 
Respectfully submitted, 
W. M. ESTEN. 
