Résumé:
Lactic acid bacteria are naturally part of our environment and our food, they have acquired
great importance through their presence in the food industry. In this study we selected 7
isolates of the genus Lactobacillus from raw cow milk in order to study their technological
abilities. The milk sample was collected in the Sayada region (Mostaganem) and the isolates
were purified and pre-identified by morphological, physiological and biochemical tests.
The results of estimation of some technological abilities indicate that all the strains present a
good acidifying and proteolytic activity. Strain 2N recorded the highest acidifying activity
with 125°D. These strains have shown other abilities such as: texturizing, flavouring and
lipolytic activity which can be exploited in the dairy industry. On the other hand, we tested
the antagonistic activity of our isolates against three pathogenic bacteria Staphylococcus
aureus, Bacillus cereus and Proteus vulgaris. According to the results we obtained, the
Lactobacillus isolates inhibited two target bacteria with inhibition zones ranging from 4mm
to 19mm.
Thus, cow's milk can be considered as an ecosystem allowing the development of a lactic
microflora with technological interest.
