No abstract

-The fatty acid composition and cholesterol content of 22 camel's milk samples from different regions of Kazakhstan were determined, in different seasons and with different camel species (Bactrian, dromedary and hybrids). Camel milk fat differed from mammalian fats by its high content of the long-chain fatty acids C14:0, C16:0, C18:0 and C18:1. Great differences in fatty acid composition occurred between regions. Short-chain fatty acids (C8:0 and C10:0) were in higher proportion in spring and long-chain fatty acids (C17:0 and C17:1) in autumn. Dromedary milk had a higher proportion of C17:0iso and C18:1 than Bactrian milk. The ratio of unsaturated/saturated acid was more favorable in camel's milk compared with that of cows or other mammalians. All of these parameters gave a nutritional advantage to camel's milk, although it had a higher content of cholesterol (37.1 mg·100 g −1 ) than cow's milk. Multivariate analysis allowed the identification of four types of fatty acid profiles with a clear opposition between the samples rich in short-chain fatty acids and the samples rich in long-chain fatty acids. These results confirmed that environmental and farming conditions allowed modulation of the lipid composition of camel's milk.

Lactoferrin (Lf) and IgG were estimated in camel's milk from Kazakhstan, where 2 species of camels (Camelus bactrianus, Camelus dromedarius) and their hybrids cohabit. The concentrations of Lf and IgG were determined according to 3 variation factors: region (n = 4), season (n = 4), and species (n = 5; sample 4 was mixed milk and sample 5 was of unknown origin). The mean values in raw camel's milk were 0.229 +/- 0.135 mg/mL for Lf concentration and 0.718 +/- 0.330 mg/mL for IgG concentration. The seasonal effect was the only significant variation factor observed, with the highest values in the spring for Lf and in the winter for IgG. The Lf concentration varied in 1-wk postpartum milk from 1.422 to 0.586 mg/mL. The range in IgG concentration was wide and decreased from 132 to 4.75 mg/mL throughout the 7 d postpartum, with an important drop after parturition. In fermented milk, the lactoproteins are generally hydrolyzed. For milk samples from undefined species, discriminant analyses did not allow the origin of the species to be determined. A slight correlation between Lf and IgG concentrations was observed in raw milk. The values were slightly higher than those reported in cow's milk, but this difference was insufficient to attribute medicinal virtues to camel's milk.