UNITED STATES DEPARTMENT OF AGRICULTURE 



BULLETIN No. 319 



Contribution from the Bureau of Animal Industry 

 A. D. MELVIN, Chief 



£\Jy>^mSu 



Washington, D. C. 



PROFESSIONAL PAPER. 



January 10, 1916 



FERMENTED MILKS. 



By L. A. Rogers, 

 Bacteriologist in Charge of Research Laboratories, Dairy Division. 



CONTENTS. 



Page. 



[ntroduction 1 



Therapeutic value of fermented milk_ 2 



Food value of fermented milk 7 



The various forms of fermented milk. 

 Bibliography 



Page. 



25 



INTRODUCTION. 



Within recent years there has been a rapidly growing interest in 

 the therapeutic value of buttermilk and other fermented milks, such 

 as kefir, kumiss, and yogurt. This is seen in the increasing sale of 

 buttermilk, in the large number of special preparations now offered 

 for sale, and in the frequent discussion of this subject in popular 

 and scientific publications. Buttermilk is not only consumed in large 

 quantities as a beverage, but is recommended by physicians as a 

 therapeutic agent in the treatment of intestinal disorders, and is in 

 constant use in many hospitals. 



It is the aim of this paper to give the reader a brief resume of 

 our present knowledge of this subject. The literature relating to fer- 

 mented milks is already voluminous, and few persons, not even phy- 

 sicians, are so situated that this can be brought together and assimi- 

 lated. It will be necessary for the benefit of those having a profes- 

 sional interest in the subject to include information of a somewhat 

 technical nature. 



All the more familiar fermented milks are the result of an acid fer- 

 mentation in which the sugar of the milk is split up into lactic acid. 

 This may be brought about by the presence in the milk of varieties of 

 the common lactic-acid group of bacteria, or, as in the case of yogurt, 

 by special organisms: or a yeast may be present, adding an alcoholic 

 to the ordinary acid fermentation. 

 8050*— Boll. .'510- 



