Influence of fatty acid composition and stereochemistry of triacylglycerols on physical properties of milk fat
Daylan Amelia Tzompa-Sosa
daylan.tzompasosa@wur.nl
Supervisors:
Prof. Dr. Ir. Toon van Hooijdonk (WUR) Dr. ir. George van Aken (NIZO Foods Research) Ir. Hein van Valenberg (WUR) Dr. Ir. Henk Bovenhuis (WUR) Dr. ir. Martijn Oversteegen (Friesland Campina) Dr. ir. Jeroen Heck (Friesland Campina)
Ir. Philip Steketee (Q Lip Laboratory)
Project term:
September 2010 - August 2014
Sponsor:
CONACYT (Consejo Nacional de Ciencia y Tecnología)
Mexican Government
Introduction
Selective breeding and feeding make a significant contribution to changes in the fatty acid composition of bovine’s milk fat (1,2) . A change in the fatty acid composition leads to a change in the physical properties (polymorphic transitions and melting behavior) of milk fat; it can be expected that fatty acid modifications will lead to a rearrangement of the TAG molecule which will also influence the physical properties of milk fat. A shift in the stereochemistry of TAGs may also have an effect in the digestion and absorption of fatty acids, especially in new born babies (3). In addition, a different stereochemistry in the triacylglycerol molecule may influence lipoprotein lipase activity.
Milk fat with different physical profiles and various stereochemistry structures are needed in the dairy industry in order to develop functional products. These different profiles could be obtained in a natural way by selective breeding and feeding.
Aim
Find the influence of DGAT1 on the variation of the sn-position within the TAG molecule and its effect on physical behavior of milk fat.
Find the relation between region-specific structure of the TAG and its influence on milk Lipoprotein lipase activity.
Research
Milk fat with different genetic profiles will be submitted to physical and chemical analysis. As part of the physical analysis, crystallization behavior and melting behavior will be studied. The regio- and stereo-specific profile of this fats will also be determined. This research will try to establish the influence of genetics on the physical properties of bovine milk fat and its relation with the stereochemistry of fatty acids within the TAG. With this knowledge, bovine MF could be modified for different needs.
Individual milk samples with known lipase activity will be subjected to a regio-specific analysis to determine the influence of the fatty acids present in the outer position of the TAG molecule with the lipase activity in the milk.
References
1. Shennink,A., Stoop, W.M., Visker, M.H.P.W., Heck J.M.L., Bovenhuis, H., van der Poel. J.J., van Valenberg, H.J.F., and van Arendonk, J.A.M. 2007. DGAT1 underlies large genetic variatin in milk-fat composition of dairy cows. Anim Genet 38:467-473 2. Smet, K., K. Coudijzer, et al. (2010). "Crystallization behavior of milk fat obtained from linseed-fed cows." Journal of Dairy Science 93(2): 495-505. 3. López-Lópeza, A; Castellote-Bargallóa, A.I; Campoy-Folgosob, C ; Rivero-Urgelc, M; Tormo-Carnicéd, R; Infante-Pinad, D; López-Sabater, M.C. 2001. The influence of dietary palmitic acid triacylglyceride position on the fatty acid, calcium and magnesium contents of at term newborn faeces. Early Hum Dev; 65suppl:s83-s94
