306 MILK AND MILK PKODUCTS. XIV. 



glyceryl salt or whether two or three different acid radicals 

 may be attached to the same glyceryl group is uncertain. The 

 latter hypothesis is probably more correct. 



The proportions of the various fatty acids found in butter 

 are subject to considerable variation according to the food ; 

 they are said also to vary with the season of the year. The 

 fat of milk given by cows soon after calving is said to be much 

 richer in volatile fatty acids than that of cows in the later 

 stages of lactation. 



Assuming that the glyceryl salts are present as separate 

 individuals (which, as already stated, is probably not the 

 case), the chief constituents of butter fat are given by Rich- 

 mond* as follows : 



% 

 Glyceryl tributyrate, C 3 H 5 (C 4 H 7 2 ) 3 about 3-85 



tricaproate, C 3 H 5 (C fi H n 2 ) 3 3-60 



tricaprylate, C 3 H 5 (C H H 15 O 2 ) 3 O55 



tricaprate, C H H 5 (C 10 H 1!( 2 ) 8 1-90 



trilaurate, C 3 H,XC 12 H 23 O 2 ) 3 7-40 



,, trimyristate, C 3 H 5 (C 14 H 27 2 ) ,, 20-20 



tripalmitate, C 3 H 5 (C lf) H 31 2 ) 25-70 



tristearate, C 8 H 5 (C 1S H ; ^0 2 ) S ,, 1-80 



trioleate, C 3 H 5 (C 1H H 33 2 ) 3 , &c. ,, 35-00 



100-00 



According to the recent analyses of C. A. Browne ! the fatty 

 acids derived from 100 grammes of butter consisted of 



(Jrammes. 



Dihydroxystearic acid, HC 18 H.^(OH) 2 2 ... 1-00 



Oleic acid, HC 1H H 38 O 2 ... ... 32-50 



Stearic acid, HC 1H H : ^0 2 ... ... 1-83 



Palmitic acid, HC lr> H 38 O 2 ... ... 38-61 



Myristic acid, HC 14 H 27 2 ... ... 9-89 



Laurie acid, HC 12 H 23 O 2 ... ... 2-57 



Capric acid, HC 10 H 19 2 ... ... 0'32 



Caprylic acid, HC 8 H 15 2 ... ... 0-49 



Caproic acid, HC 6 H n 2 ... ... 2-09 



Butyric acid, HC 4 H 7 2 ... ... 5-45 



94-75 



Dairy Chemistry, p. 35. t Jour. Chem. Soc. 1900, abst. ii. 55. 



