Abstract

The aim of this work was to study the suitability of camel milk to transformation in Leben by lactic fermentation. Sixty strains of lactic acid bacteria (LAB) were isolated from camel milk. Strains were tested for their acidification activity, ability to use citrate, biomass yield, growth rate and Exopolysaccharide (EPS) production. Twenty-nine strains showed ability to use citrate. These strains were tested for their acidifying activity. Only seven strains present ΔpH ≥0.3 U and then were considered as rapid acidifier strains. Four strains produced EPS and two strains showed high acidification rate and high yield of biomass at the end of fermentation. The strain SLCch₁₄was the most acidifying strain (0.45 U) and had a high ability to produce an important biomass (0.98 g/l). SCC1₃₃ produced EPS and presented a satisfactory ability of acidification (0.35 U). These  strains,  tentatively  identified  by  API  50 CHL,  were divided  into  three  groups: Lactococcus lactis, Lactobacillus pentosus, Lactobacillus plantarum, Lactobacillus brevis and Pediococcus pentosaceus. These strains were applied to prepare Leben from camel milk. In order to study the potentiality of the starter to ferment other types of milk goat milk was chosen. The pH and total acidity of the final product were 3.93; 5.30 and 110; 43 D° for camel and goat respectively. The rheological study showed that Leben present a non-Newtonian and thixotropic behaviour.

Key words: Camel milk, goat milk, Leben, lactic acid bacteria, fermentation.