UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 319 
Washington, D. C. 
Issued January 10, 1916 
Revised November, 1928 
FERMENTED MILKS 
By L. A. Rogers, Principal Bacteriologist 
Revised by W. R. Albus, Associate Bacteriologist, Bureau of Dairy Industry 1 
CONTENTS 
Page 
Introduction 1 
Therapeutic value of fermented 
milks 2 
Food value of fermented milks 6 
Various kinds of fermented milk 7 
Buttermilk 7 
Acidophilus milk 11 
Page 
Various kinds of fermented milk — 
Continued. 
Kefir 15 
Kumiss 18 
Yogurt 20 
Bibliography 23 
INTRODUCTION 
In late years there has been a steady increase in the consumption 
of buttermilk and other fermented milks. These milks are very 
wholesome and refreshing as beverages, and their value as foods is 
unquestionable. Many popular and scientific articles on the thera- 
peutic value of sour milk have appeared from time to time. Such 
publicity is, no doubt, responsible in a large measure for the increas- 
ing sale of these products. The recent development of Lactobacillus 
acidophilus milk is phenomenal, and the beneficial results ascribed 
to its use have served to stimulate a new interest in the subject of 
fermented milks. 
It is the aim of this bulletin to give the reader a brief resume of 
the present knowledge of fermented milks. The literature relating 
to this subject is already voluminous, and few persons are so situated 
as to have access to all of it. For the benefit of those having a 
professional interest in the subject information of a somewhat tech- 
nical nature has been included. 
All the familiar fermented milks are the result of an acid fermen- 
tation in which the sugar of the milk is split up into lactic acid and 
other products. This may be brought about by the presence in the 
1 Mr. Albus resigned from the department June 16, 1928. 
1644 =>— 28- 1 
