COMPOSITION OF NATURAL FATS AND OILS 



223 



tain citrus fruit seeds. However, allowing for these slight discrepancies, 

 the princii)le of "even" distribution has been found to be applicable to most 

 land \egetable fats, to the fats from aquatic flora and fauna (which in- 

 clude the larger fishes and marine animals) and to the fats of many land 

 animals. 



20 40 60 80 



SATURATED FATTY ACIDS, 

 MOL PERCENT OF TOTAL FATTY ACIDS 



100 



Fig. 2. Calculated composition of triglyceride mixtures containing satu- 

 rated and unsaturated fatty acids distributed at random: (1) triunsatu- 

 rated glycerides; (2) trisaturated glycerides; (5) monosaturated-diunsatu- 

 rated glycerides; (4) disaturated-monounsaturated glycerides.''** 



(c) Theory of Random Distribution. A third theory to explain triglyc- 

 eride constitution, namely, that of random distribution, was originally 

 suggested by Hilditch and his associates^^^-^^^--^^ as applicable to certain 

 animal fats which did not fit in with the scheme of even distribution. This 

 is also knowTi as chance or "indiscriminate" distribution. According to 

 this theory, the fatty acids are believed to combine with glycerol in ac- 

 cordance with chance. The distribution of the fatty acids in the various 

 types of glyceride molecules may readily be calculated. In the case of the 

 simple triglycerides, the amount which should be present on a random basis 

 amounts to S' (for GS3) or U' (for GU3). 



There are two main classes of animal fats which seem to conform to this 



»« A. Banks and T. P. Hilditch, Biochem. J., 25, 1168-1182 (1931). 

 ««^ A. Banks and T. P. Hilditch, Biochem. J., 26, 298-308 (1932). 

 ^* E. W. Eckev, Ind. Eng. Chem., 4O, 1183-1190 (1948). 



