29 



farina, only one subject went through both experiments, and two new 

 subjects were brought into the second part of the digestion experiment, 

 thus somewhat destroying the value of the results. 



One point worthy of special notice with all the foods is that the long 

 cooking has not increased the percentage digestibility of the carbohy- 

 drates materially, and that the chief difference is found in the protein 

 column. This is especially true with the oatmeals. On page 30 it was 

 shown that long cooking increased the solubility of the proteid bodies 

 of these materials, and this has doubtless influenced their digestibility. 

 It will be remembered that twenty minutes' cooking rendered about twice 

 as much of the total solids of wheat meals soluble in water as with the 

 oatmeals. Apparently this has not increased the completeness of the 

 digestion of these foods, although it may have rendered them more easily 

 acted upon by the digestive juices. 



It is true that the percentage increase in the digestibility of the 

 foods when cooked for the longer period is not very large, and possibly 

 the additional amount of nutrients represented would not be sufficient to 

 warrant the longer cooking; but it must be remembered that the amount 

 of energy required to digest the food will probably be lessened, and the 

 palatability of the food will be improved. In general, it may be argued 

 from the results presented that the longer cooking slightly improved the 

 completeness of digestion, and probably ease of digestion and palatability, 

 making them good nutritious foods, even for those with weak digestion 

 powers. This is especially true of the oatmeals. 



Palatability. 



Thorough relish for food is without doubt a factor which must be 

 taken into consideration when we come to deal with digestibility. The 

 secretion of the digestive juices which attack the ingested materials is 

 largely under the control of the nervous system, and, therefore, it is rea- 

 sonable to believe that the enjoyment of eating stimulates the secretory 

 power of the glands which furnish them. No energy or nutritive value is 

 added to a food by reason of its agreeable flavor or tasty appearance, but 

 the amount of it which is finally appropriated by the body for the pur- 

 pose of nourishment may be greatlv increased thereby. It is held by 

 some persons that dyspepsia is often contracted by reason of partaking 

 of food which is not wholly relished, even though it is highly nutritious 

 and well cooked. Palatableness of a food, therefore, determines to a 

 great degree the amount of nutrients which will be extracted from it by 

 the digestive organs. When anticipation alone sometimes "makes the 

 mouth water," the potence of this factor is clearly and practically demon- 

 strated. 



These foods are rendered palatable by processes of parching, boiling, 

 malting, and, in some cases, by the addition of other materials. That 



