South African Journal of Chemistry
On-line version ISSN 1996-840X
Print version ISSN 0379-4350
OSTHOFF, Gernot; HUGO, Arno; JOUBERT, Chris C. and SWARTS, Jannie C.. DSC of milk fats from various animals with high levels of medium-chain, unsaturated and polyunsaturated fatty acids. S.Afr.j.chem. (Online) [online]. 2011, vol.64, pp.241-250. ISSN 1996-840X.
Mammals of different species provide milk lipids with a wide variety of fatty acid composition yet with common stereospecific features. This allows the investigation of crystallographic properties of milk lipids that cannot be achieved by interesterified lipids due to the random stereospecific distribution that is obtained. The milk fats of elephant and white rhinoceros contain high amounts of 8:0, 10:0 and 12:0 which form triglyceride species that melt between 8 and 22 °C. The crystallographic behaviour of the milk lipids from blesbok and blue wildebeest differ from the other ruminant lipids, and that of horse and vervet monkey differ from the other non-ruminant lipids. It seems that a low content of 18:0 and 18:1, and a high content of saturated short- to medium-length fatty acids prevent the formation of the high and low temperature melting isotherms, between 35 and 42 °C, and between -45 and -10 °C, respectively, which are normally observed for milk fats.
Keywords : Triglyceride; differential scanning calorimetry; milk; medium-chain fatty acid; polyunsaturated fatty acid.