Triacylglycerol structure

Cocoa butters have a natural variation in physical properties related to the triacylglycerol structure Malaysian, Indian and Indonesian butters are harder than those from Africa, and Brazilian butters are the softest. The hardness of typical butters from some continents has changed over the years (Timms and Stewart, 1999). Because the hardness affects the processing required for chocolate manufacture, suppliers of cocoa butter to that trade blend butters to attempt to produce a uniform product. 

Lawson, L.D. and Hughes, B.G. (1988) Triacylglycerol structure of plant and fungal oils. Lipids, 23,... 

Solvent-free enzymatic interesterification of milk fat alone or with other fats or fatty acids provides the most acceptable route for modification of the triacylglycerol structures in milk fat and further research and development in this field is expected to provide physical and physiological benefits. From a nutritional perspective, it is of interest to examine the effects of randomized milk fat on serum cholesterol. Christophe et al. (1978) reported that substitution of native milk fat with chemically-randomized interester-ified milk fat reduced cholesterol levels in man. However, others found that there was no effect on serum cholesterol levels in man as a result of substitution of ezymatically randomized milk fat (De Greyt and Huyghebaert, 1995). Further studies are required to determine if interesterilied milk fat provides a nutritional benefit. 

The major differences between the lipids of bovine and human milk are in fatty acid composition and triacylglycerol structure. Bovine milk contains substantial quantities of C4 o-Ci0 o, about 2% Cis 2 and almost no other long-chain polyunsaturated fatty acids. The fatty acid composition is not altered by ordinary changes in diet. Human milk contains very little C4 o-C10 o, 10-14%i (w/w of fat) Ci8 2, and small quantities of other polyunsaturates. The triacylglycerol structure differs, with much of the sn-2 position in human milk lipids occupied by C16 0 and the sn-2 position of bovine milk-fat occupied by C4 o-Ci0 o-... 

This difference is likely caused by the different triacylglycerol structures of safflower and sunflower oil. 

Interest in the triacylglycerol structure of peanut oil arose from observations that peanut oil showed atherogenic effects in rabbits and other animals (144—147). This atherogenicity has been attributed to the triacylglycerol structure of peanut oil (148-150) because treatment of peanut oil with a base, to bring about randomization, reduced the atherogenicity to that of corn oil (151). However, the results of the Kritchevsky studies (148, 149, 151) have been questioned (40) on the basis that they did not include other vegetable oils for comparison and a lack of data for appropriate statistical analysis. More recent studies (152-155) have shown that peanut oil and peanut product-based diets produce a reduction in total and LDL cholesterol. 

Distance and dihedral angle calculations on triacylglycerol structures using energy minimization molecular modeling approach were able to explain the relative crystallization tendency of vegetable oils in the bent fork conformation (61). 

Van Langevelde, A.J., Triacylglycerol Structures and Cocoa-Butter Crystallization, Ph.D. Thesis, University of Amsterdam, 2000, pp. 91-110. 

Jensen, M.M., Christensen, M.S., and Hoy, C.E., Intestinal absorption of octanoic, decanoic and linoleic acids effects of triacylglycerol structure, Ann. Nutr. Metab., 38, 104, 1995. 

In most cases, the triacylglycerol structure in terms of saturation is more useful in interpreting the physical properties of an oil and, for CNO, this was... 

Sanders, T.H. (1979) Varietal differences in peanut triacylglycerol structure. Lipids, 14, 630-633. 

Refined olive oil. This oil, which is obtained from virgin olive oil by refining methods which do not lead to alteration in the initial triacylglycerol structure, has a maximum acidity, in terms of oleic acid, of 0.5 g/100 g. 

Santinelli, F., Damiani, R and Christie, W.W. (1992) The triacylglycerol structure of olive oil determined by silver ion high performance liquid chromatography in combination with stereospecific analysis. J. Am. Oil Chem. Soc., 69, 552-557. 

Christensen, M.S., Hoy, C.E., Becker, C.C., and Redgrave, T.G. 1995. Intestinal absorption and lymphatic transport of eicosapentaenoic, docosahexaenoic, and decanoic acids dependence on intramolecular triacylglycerols structure. Am. Clin. Nutr. 61 56-61. 

Pufal, D.A., Quinlan, P.T., and Salter, A.M. (1995) Effect of Dietary Triacylglycerol Structure on Lipoprotein Metabolism A Comparison of the Effects of Dioleylpalmitoylglycerol in Which Palmitate Is Esterified to the 2 or l(3)-Position of the Glycerol, Biochim. Biophys. Acta 1258,41 8. 

Karupaiah, T. and Sundram, K. (2007). Effects of stereospecific positioning of fatty acids in triacylglycerol structures in native and randomized fats a review of their nutritional implications. Nutrition Metabolism, 4,16. 

Straarup, EM Lauritzen, L Faerk, J Hoy, C-E Michaelsen, KF. The Stereospecific Triacylglycerol Structures and Fatty Acid Profiles of Human Milk and Infant Formulas. 

Berry, SEE. Triacylglycerol structure and interesterification of palmitic and stearic acid-rich fats an overview and implications for cardiovascular disease. Nutr Res Rev, 2009 22 3-17. 

Yli-Jokipii K, Kallio H, Schwab U, et al. Effeets of palm oil and transesterified palm oil on chylomicron and VLDL triacylglycerol structures and postprandial lipid... 

Figure 5 Reversed phase HPLC (linear gradient of 10-90% isopropanol in acetonitrile at 25°C) of natural (top) and rearranged (bottom) butterfat triacylglycerols as obtained with light-scattering detector. Peak identification by carbon and double bond number. (Reproduced with permission from Marai L, Kuksis A, and Myher JJ (1994) Reversed-phase liquid chromatography-mass spectrometry of the uncommon triacylglycerol structures generated by randomization of butteroil. Journal of Chromatography A 672 87-99.)...

Fig. 2.10. Triacylglycerol structure (modified from Stymne and Stobart, 1987 used with permission of the copyright owner, Academic F York).

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