928 XIV. NUTRITIONAL VALUE OF FATS 



tiires, are concernod, the acetyglycerides were found to l)e as satisfactory 

 as ordinary fats of comparable degrees of unsaturation. 



Several types of acetylated glycerides are possible, namely monoacetyl 

 and diacetyl glycerides. The terms "monoacetins" and "diacetins" are 

 widely used to indicate the composition of these glycerides. Baur"" pro- 

 posed the term "acetin fats" to cover this group of compounds. 



The preparation and use of acetoglycerides containing predominantly 

 oleic acid as the fatty acid with a high molecular weight were described by 

 Feuge and co-workers. ^"-^ Baur also reported on the preparation and proper- 

 ties of diacetin fats from common vegetable oils (soj'bean, cottonseed, rape- 

 seed, and coconut oils).'"'^''*''^ The most useful property of the fats formed 

 by the introduction of the acetyl group into the glyceride molecules is the 

 pronounced lowering of the melting point which occurs. ^"^ Up to the time 

 of the discovery of the acetoglycerides, a low-melting fat consisted of either 

 an unhydrogenated oil or of one only slightly hydrogenated. These fats 

 contain such large amounts of highly unsaturated acids that they do not 

 have stability toAvard oxygen or the keeping quality necessary for their 

 extensive use. This fact has limited their employment in the production 

 of plasticizing coatings. Thus acetoglycerides with a high degree of satura- 

 tion and a significantly increased resistance to oxidation may be prepared 

 which can replace the more perishable unsaturated fats having similar 

 melting points.^'"' 



One possible use for the acetin fats is as a coating for processed meats, 

 and for cheese, to retard loss of moisture and deterioration.'"'^ They may 

 also be used to coat hard candies, raisins, and nuts. The primary require- 

 ment here is for an oil which will not become rancid when a thin film is 

 exposed to air for long periods of time. Acetostearin products are stable to 

 oxidation, especially if they are deriA'ed from completely hydrogenated 

 vegetable oils which contain natural antioxidants.^"* It is possible that 

 mixed acetin fats may be substituted for normal fats as salad oils and 

 spreads when improved keeping quality is essential.'"'* After complete 

 hydrogenation, which renders them immune to oxidation and rancidity, 

 they still retain the waxlike softness necessarj^ for their use as spreads or 

 salad dressings. -""^ 



In tests of the solubilitj^ of hard fats in liquid oils, which is also of im- 



«" F. J. Baur, J. Am. Oil Chemkts' Soc, 31, 147-151 (1954). 



«* R. O. Feuge, A. T. Chos, and E. J. Vicknair, J. Am. Oil Chemists' Soc, 30, 320-:i25 

 (1953). 



^o« F. J. Baur, /. .4m. Oil Chemists' Soc, 31, 196-199 (1954). 

 «' R. O. Feuge, Food Eng., 25, N. 6, 100-103 (June, 1953). 

 «8 R. O. Feuge, Food TechnoL, 9, 314-318 (1955). 



