Semuda is a cheese produced in a restricted Italian alpine area (north of Como lake). The aim of the research was to study the characteristics of the indigenous lactic acid bacteria (LAB) population. A total of 78 LAB strains were isolated from ripened cheese and identified using species-specific primers and 16SrRNA gene sequencing. Randomly amplified polymorphic DNA (RAPD) analysis was used to evaluate the genotypic diversity, while technological properties of major interest for cheese-making (acidification and caseinolytic activity) were also evaluated. The predominant species, were Enterococcus faecalis, Lactobacillus paracasei subsp. paracasei and Lb. plantarum. Three bacteriocin producers were found belonging to Eenterococcus spp. and enterocin A and P genes were detected.
La Semuda è un formaggio a latte crudo tradizionale lombardo prodotto nell'alto Lario occidentale (provincia di Como). In questo lavoro è stata valutata la composizione della microflora lattica autoctona a fine stagionatura di questo formaggio. Settantotto ceppi di batteri lattici (LAB) sono stati identificati utilizzando PCR specie-specifica ed il sequenziamento di una porzione del gene 16SrRNA. I ceppi sono stati tipizzati geneticamente mediante RAPD-PCR e caratterizzati in base a caratteristiche colturali e tecnologiche, quali attività acidificante e attività caseinolitica. Le specie predominanti sono risultate Enterococcus faecalis, Lactobacillus paracasei subsp. paracasei e Lb. plantarum. Tra gli isolati 3 ceppi, appartenenti al genere Enterococcus, sono risultati produttori enterocina A e P.
Microbial profile of Semuda cheese and genotypic, phenotypic and technological characterization of indigenous lactic acid bacteria.
Stefano Morandi;Milena Brasca;Roberta Lodi
2010
Abstract
Semuda is a cheese produced in a restricted Italian alpine area (north of Como lake). The aim of the research was to study the characteristics of the indigenous lactic acid bacteria (LAB) population. A total of 78 LAB strains were isolated from ripened cheese and identified using species-specific primers and 16SrRNA gene sequencing. Randomly amplified polymorphic DNA (RAPD) analysis was used to evaluate the genotypic diversity, while technological properties of major interest for cheese-making (acidification and caseinolytic activity) were also evaluated. The predominant species, were Enterococcus faecalis, Lactobacillus paracasei subsp. paracasei and Lb. plantarum. Three bacteriocin producers were found belonging to Eenterococcus spp. and enterocin A and P genes were detected.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
