Characterization of lactic acid bacteria isolated from an Italian dry fermented sausage

Abstract

Studies were carried out on the microbiological changes which occurred during the ripening of an Italian dry fermented sausage, manufactured without starter cultures. Lactic acid bacteria were studied using the commercially available system API 50 CH for the characterization of carbohydrate fermentation patterns. The results obtained indicated that lactobacilli constituted the predominant fl ora throughout the ripening period. Characterisation of 90 lactic isolates indicated that microfl ora was dominated by facultative heterofermentative lactobacilli: approximately 51,1% of them could be identifi ed as Lactobacillus sakei. The API 50 CH identifi cation system did not prove to be reliable: 10% of the isolates remained unidentifi ed and softwareʼ response for L. sakei subs. sakei reference strain was Lactococcus lactis subsp. lactis. In this way, this species could not be positively identifi ed solely by means of the match index, but must be associated with other phenotypic or genotypic characters.