18 Milk and Its Products 



per cent of fat is recorded from any cow giving as 

 much as 15 pounds of milk per day. Any analysis 

 above 7 per cent is extremely rare, and should be 

 regarded with suspicion unless well authenticated. 

 The mixed milk of herds seldom falls below 3 per 

 cent of fat and rarely rises above 5.5 per cent. 



Colostrum. The first milk secreted by the animal 

 after parturition is quite distinct in composition and 

 physical properties from that produced after the 

 secretion has become well established. Such milk 

 is called colostrum, and is ordinarily considered 

 unfit for consumption or manufacture. Colostrum 

 differs from normal milk chiefly in its less proportion 

 of water and sugar, in the much greater proportion 

 of albumin and ash, in the extremely variable amount 

 of fat, and in the presence of small organized bodies 

 known as colostrum corpuscles, which are probably 

 debris of the cell structure of the gland. The follow- 

 ing analyses from Richmond after Vaudin show the 

 extremely variable composition of colostrum: 



No. 1. No. 2. 



Water -'>' 72 - 39 75 - 51 



Pat . . . . " 1.30 6.32 



Sugar 1.52 2.17 



Proteids (casein, albumin, etc.) 23.70 14.91 



Ash 1.09 1.09 



100.00 100.00 



The percentage of albumin in colostrum is so 

 great that it will cause the whole mass of milk to 

 thicken upon boiling, and this is ordinarily consid- 

 ered a sufficient test for determining the suitability 

 of the milk for consumption or manufacture. With- 



