PHYSICAL PROPERTIES OF MILK 



89 



of the animal, and possibly the period of lactation as minor 



influencing factors. 



Influence of feed on the color of milk whey. 



In addition to the foregoing studies it was considered advisable 

 to study the influence of the food of the cow upon the color of the 

 whey. This would seem to be especially important in view of 

 the fact that in a contemporaneous * investigation the food was 

 found to be the important factor in the pigmentation of the milk- 

 fat. 



The color of the milk whey was observed with two different 

 cows in two different succeeding periods in which the food had 

 been varied primarily for the purpose of studying the effect upon 

 the color of the milk-fat. The results are given in the follow- 

 ing: 



Influence op Feed upon the Color op Milk Whey 



Cow No. 



Period 



Feed 



Color 

 op Fat 



Color 

 op Whey 



57 



57 



1 



2 



Bleached clover hay and 

 white corn .... 



Green alfalfa hay and 

 yellow corn .... 



1 inch layer 

 Yellow 



8.0 



^£5.0 



10 cm. layer 

 Yellow 



3.5 

 4.5 



301 

 301 



1 

 2 



Green alfalfa hay, corn 

 silage and grain . . 



Bleached timothy hay 

 and white corn . . . 



Yellow 



32.0. 

 1.3 



Yellow 



5.5 

 3.0 



The results of these two cases might seem to indicate that 

 some feeds influence the color of the whey as well as the color 



1 Missouri Agricultural Experiment Station Research, Bulletin No. 

 10 (1914) ; Jour. Biol. Chem. 17, p. 191 (1914). 



