Characterization Of Algerian Raw Camel’s Milk : Identification Of Dominant Lactic Acid Bacteria And Proteins Analysis

Résumé: The chemical composition of Algerian raw camel’s milk is slightly rich in fat 34.4 ± 2.8 g.l-1, proteins 33.1 ± 2.1 g.l-1, lactose 45.1 ± 3.1 g.l-1, ash 8.15 ± 0.15 g.l-1 and total solids 122.6 ± 0.12 g.l-1. This composition varied by several factors such as feeding, breeds, milk yielding and the health of the animal. Our results showed that total casein proteins were higher than whey proteins. SDS-PAGE showed that casein proteins of camel’s milk and cows’ milk have the same molecular weight, about 24 kDa. The whey proteins of camel’s milk were presented by 5 bands. Compared with cow’s milk, camel’s milk contents a little amount of β-lactoglobuline. The pH of raw milk decrease from 6.5 to 5.4 after 72 h of incubation at 30°C. The total count of lactic acid bacteria can reach 200 x 106 cfu ml-1 in MRS medium. Fourty strains of lactic acid bacteria were isolated from camel milk. The mesophilic group were represented by Lactococcus lactis subsp. lactis biovar. diacetylactis which is the dominant strain, L. lactis subsp. Lactis, L. lactis subsp. cremoris and L. lactis subsp. lactis biovar. diacetylactis produce more than 100 mM of lactic acid after 24 h of incubation at 30°C. The thermophilic strains were represented by two species, Streptococcus thermophilus and Enterococcus faecalis. From a technological point of view, the camel milk can be used as a source of new starters in the development of the industrial manufacture of these strains.

Publié dans la revue: Journal Algérien des Régions Arides