DIGESTIBILITY OF SOME ANIMAL FATS. 



19 



which was eaten on an average. No physiological disturbance was 

 noted with the other fats tested. Such matters have a practical 

 value in discussing dietetics, aside from the theoretical question 

 whether this laxative property is ascribable to differences in the 

 chemical structure of the fats or to some other factor. 



The average coefficient of digestibility of brisket fat is higher than 

 that previously found for beef (kidney) fat (93 per cent)/ which is in 

 accordance with the observation that the digestibility is inversely 

 proportional to the melting point. The other fats studied were either 

 fluid or had a melting point not far from room temperature, so it was 

 not surprising to find that they did not show marked variations in 

 thoroughness of digestion. 



The average digestibility of carbohydrates in the dijfferent tests was 

 found to vary only from 96.1 to 96.9 per cent, while the digestibility 

 of this food constituent in the average mixed diet has been found to 

 be 97 per cent.^ This close agreement would indicate that the con- 

 sumption of fat did not exercise any unusual effect upon carbohydrate 

 digestion. 



As a whole, the results of the digestion experiments indicate that 

 chicken fat, goose fat, brisket fat, cream, egg-yolk fat, and fish fat 

 are all well assimilated and that they are satisfactory sources of fat 

 for the dietary. Since butter fat eaten in the foT-m of cream and 

 egg-yolk fat are very thoroughly digested and easily obtainable and 

 apparently contain or carry with them accessory food substances 

 necessary in the diet for growth and general well-being, a wide use of 

 these two fats in the dietary is especially desirable. 



1 U. S. Dept. Agr. Bul.'SlO, p. 21. 



2 Coimecticut Storrs Sta. Rpt. 1901, p. 245. 



