172 STORRS AGRICULTURAL EXPERIMENT STATION. 
not be classed in the same group, because the nutrients are 
so different in kind. Leaving out of account the flavor, and 
considering simply the value for nourishing the body, butter, 
lard, salt pork, and olive oil would be very similar. ‘The same 
would be true of wheat flour, corn meal, and rice, all of which 
contain nearly the same proportions of protein, fats and carbo- 
hydrates, although the protein in wheat flour is slightly larger 
in amount than in the other materials mentioned. 
In what has been said no account has been taken of the 
digestibility or availability of the food. By digestibility, as 
the word is ordinarily used, two things are really meant. One 
is the proportion which can be digested and thus made avail- 
able to the body. For this the term availability would be 
better, as stated on page 156 above. ‘The other has to do with 
the fitness of the food for the use of the particular individual 
who eats it. For most people milk is a very wholesome article 
of diet. Some cannot take it without discomfort. It does not 
‘““agree’’ with them. Eggs are likewise a very nutritious 
article of food, but they disagree with many people. In com- 
mon parlance foods which ‘‘agree’’are called digestible and 
those which disagree are often spoken of as undigestible. 
This difference is a matter of individuality and cannot be taken 
into account in the present discussion. The proportions of the 
different food materials that are actually digested or available 
differ more or less in different food materials. * 
The proportions of nutrients in materials commonly used as 
food have been given in previous Reports of the Station. In 
the Report for 1896 may be found a table showing the propor- 
tion of digestible or available nutrients in a considerable num- 
ber of the more common food materials. It is hoped that a 
future Report may treat more fully of the digestibility and 
availability of food. It will suffice to say here that our ordi- 
nary food materials differ much less in the availability of their 
nutrients than is commonly supposed. | 
GROUPING OF FOOD MATERIALS BY NUTRITIVE VALUES. 
For practical purposes it will be convenient to classify the 
more common food materials in groups according to their nutri- 
tive values. Sucha classification is attempted in table 43 beyond. 
The grouping is made with reference to the menus beyond. 
In each group the different members have very nearly the 
* See statements regarding this subject in previous article. 


