228 THE BUTTER INDUSTRY IN UNITED STATES [452 



greatly in the extent to which they are absorbed from the 

 digestive tract under normal conditions. Such differences as 

 have been found seem to be explained by the differing hard- 

 ness or melting points of the fats. If the melting point of the 

 fat lies much above the body temperature, the fat will not be- 

 come sufficiently fluid in the intestine to be readily emulsified 

 and digested. The following data determined by Munk and 

 Arnschink are cited by Von Noorden in this connection: 



Nature of fat 



Stearin 



Mixture of stearin and almond oil 



Mutton fat 



Mutton fat 



Lard 



Bacon fat 



Goose fat 



Olive oil 



Per cent lost in feces 



86-9 1 



10.6 



9.2 



7-4 

 2.6 

 2.8 

 2.5 

 2-3 



These results show good utilization and no significant dif- 

 ferences in digestibility among fats melting at or below 43 de- 

 grees C. while with melting points from 49 degrees to 55 de- 

 grees C. the losses were considerable, and with stearin melting 

 at 60 degrees C. much the greatest part failed of digestion. 

 Notice, however, that the admixture of sufficient almond oil 

 to lower the melting point a few degrees resulted in very 

 greatly increased digestibility. Hence while stearin eaten alone 

 is only slightly digested, yet fats containing much stearin may 

 be digested very well provided they also contain enough olein 

 so that the melting point of the mixture as a whole is not much 

 above body temperature. Since oleomargarine contains not- 

 ably more stearin than butter it was at one time thought that 

 it might show correspondingly larger losses in digestion; but 

 repeated experiments have shown that oleomargarine (being 

 made so as to have the same hardness) shows practically the 

 same losses in digestion as does butter. Thus in experiments 



