Lactic acid bacteria isolated from raw milk of Guirra ewes were characterised from a technological point of view, in order to select the suitable strains for their use as a cheese starter. Lactococcus lactis subsp. lactis, which represented more than 67% of the fast acid-producer bacteria in raw milk, exhibited no differences in their acidifying activity after 24h of incubation. Most lactobacilli were weak acid-producers, showing a great variation in their acidifying activity. Four strains of Lactobacillus paracasei subsp. paracasei, 1 of Lb plantarum and 1 of Lb. pentosus exhibited high proteolytic capacity. Enzyme activity (API-ZYM assay) of lactococci and lactobacilli was generally low. Lactobacillus spp. all showed esterase and esterase-lipase activity, and in general, they had higher aminopeptidases values than those observed in L. lactis subsp. lactis. There was no endopeptidase activity in any of the lactococci tested, but most lactobacilli showed slight α-chymotrypsin activity. Alkaline phosphatase was not detected among the lactococci and lactobacilli, but acid phosphatase activity was observed.
|Translated title of the contribution||Technological characterisation of lactic acid bacteria isolated from raw ewes' milk for cheese making|
|Original language||Multiple languages|
|Publication status||Published - 31 Oct 2006|
- 56 Lactic acid bacteria (ewes' milk, technological characterization)