924 XIV. NT'TT^TTIONAL VALT'E OF FATS 



4. The Nutritional Value of Modified Fats and Oils 



(1) Monoglyccridcs and Diglijcerides ' 



Although it is generally agreed that mono- and diglycerides are inter- 

 mediates in fat digestion and in fat al)sorption, as well as in its intermediary 

 metabolism, experimental evidence on the subject has only recently become 

 available. These compounds have been known since they were synthesized 

 by Berthelot in 1860.^'^^ Moreover, mixtures of mono- and diglycerides 

 have been produced industrially for many j'ears by reacting good fats, 

 chiefly triglycerides, with glycerol according to patents of Edeler and 

 Richardson issued in 1934 and 1940.^^° These materials had been widely 

 used as food additives during the period between 1928 and 1932. It was 

 found that the addition of these commercial products in amounts of one 

 to two parts per hundred brought about a modification of the so-called 

 "functional properties" of both margarine and shortening. According to 

 the report of the Food Protection Committee of the National Research 

 Council, ^^^ toda}', in the Ignited States, almost every major l)rand of retail 

 shortening contains about 2% of added monoglycerides and about 2% of 

 added diglycerides. Shortenings used by bakers for cake making contain 

 over 3% of each of these components, and some shortening products de- 

 signed for use in baking bread contain as much as 7 to 10% of added mono- 

 glycerides and a like amount of added diglycerides. Mono- and diglycerides 

 are used to a somewhat lesser extent in margarine; a maximum of 0.5% is 

 allowed by the Federal Standard of Indentity for Oleomargarine. ^^^'^^^ 

 Some experimental evidence indicates that mono- and diglycerides are 

 effectively utilized by the animal body. Thus, Braun and Shrewsbury**' 

 noted that monostearin and monolinolein were nutritionally approximately 

 equivalent to lard in producing growth in rats when fed at a level of 8%. 

 In 1951 Ames and his co-workers''** reported no difference in growth, repro- 



"^ M. Berthelot, Chimie organiqxe fondee sur la synthese, 2, 68-100 (I860); cited by 

 B. F. Daubert and C. G. King, Chem. Revs., 2!i, 269-285 ( 1941 ) p. 271. 



380 A. Edeler and A. S. Richardson (to Procter and Gamble), U. S. Patents Nos. 2,206,- 

 167 and 2,206,168 (July 2, 1940); Canadian Patents, Nos. 340,803-340,80.5 (April 10, 

 1934). 



^^ Anonymous, The Safety of Mono- and Diglycerides for Use as Intentional Additives in 

 Foods, Report of Food Protection Committee, Nat. Research Covmcil, Pub. No. 251, 

 1-14 (Dec, 1952). 



^^ Anonymous, Oleomargarine. Definitian and Standard of Identity, Fed. Security 

 Agency, Food and Drug Admin., Service and Regulatory Announcements, Food, Drug 

 and Cosmetic No. 2 Rev., 1, Part 45, 58-60 (Jan., 1949). ' 



383 W. Q. Braun and C. L. Shrewsbury, Oil & Soap, 18, 249-250 (1941). 



3«* S. R. Ames, M. P. O'Gradv, N. D. Embree, and P. L. Harris, ./. Am. Oil Chemist'^' 

 5oc.,;g5, 31-33 (1951). 



