UNITED STATES DEPARTMENT OF AGRICULTURE 



l^tt BULLETIN No. 507 



Washington, D. C. 



Contribation from the States Relation Service 

 A. C. TRUE, Director. 



PROFESSIONAL PAPER 



March 24, 1917 



STUDIES ON THE DIGESTIBILITY OF SOME 

 ANIMAL FATS. 



By C. F. Langworthy, Chief, and A. D. Holmes, Scientific Assistant, Office of Home 



Economics. 



CONTENTS. 



Page. 



Introduction 



Experimental methods . 



Page. 



Digestion experiments— Chicken fat, goose 

 fat, brisket fat, cream, and fat in egg ^olk 

 and ia fish 4 



Summary 18 



INTRODUCTION. 



Previous papers ^ reported the results of experiments undertaken 

 to determine the thoroughness of digestion of lard, beef fat, mutton 

 fat, butter, olive oil, cottonseed oil, peanut oil, coconut oil, sesame 

 oil, and cocoa butter, which showed that fairly large quantities of 

 these fats incorporated in a simple mixed diet could be eaten without 

 digestive disturbances and that all were well digested, the coefficient 

 of digestibility being proportional to the melting point of the fat. 

 In continuation of the study of animal and vegetable fats and their 

 dietetic uses, this bulletin reports a study of the digestibility of 

 chicken fat, goose fat, brisket fat, cream, fat in egg yolk, and fat 

 or oil in fish. 



Fats are so very similar in their chemical nature that it is natural 

 to assume that they would not differ materially with respect to their 

 food value (of which digestibihty is* an important factor) under 

 comparable conditions. While race experience would indicate that 

 this is true in the main, there is reason to believe that the question 

 of the digestibility of fats and the closely related matter of the 

 energy which they supply to the body merit further study. That 

 the digestion of different sorts is not alike in all its steps is indicated 



1 U. S. Dept. Agr. Buls. 310 (1915); 505 (1917). 

 XoTE. — This bulletin records studies of the digestibihty of chicken fat, goose fat, brisket fat, cream, fat 

 in egg yolk, and fat or oil in fish. It is primarily of interest to students and investigators of food problems. 

 70239°— Bull. 607—17 1 



