Microbiological characterization of an artisanal cheese produced from raw milk of Massese sheep was carried out in order to standardize the production. The research was conducted during 3 traditional cheesemaking processes. Samples from milk, rennet, curd and cheese at different stages of ripening (2, 7, 14, 28, 42 days) were analysed to determine the enumeration of: total mesophilic bacteria; lactococci; mesophilic lactobacilli; enterococci; yeasts and moulds; staphylococci and micrococci; total and faecal coliforms and Escherichia coli. Lactic acid bacteria remarkably increased during ripening: a very high level of lactococci was detected particularly during the first 14 days and was followed by a gradual decrease. Lactobacilli showed high levels, but lower than lactococci, during the whole ripening period. Enterococci and yeasts resulted quantitatively less important. Staphylococci and coliforms markedly decreased during ripening. Samples from rennet constantly revealed low bacterial counts. Means and standard deviations were calculated. ANOVA tables were constructed on data previously transformed according to Bartlett method. Isolation and identification of lactic acid bacteria and yeasts from the examined cheese were also carried out. 28 lactobacilli, 9 lactococci, 27 enterococci and 59 yeasts were identified. Lactobacillus plantarum, Lactococcus lactis subsp. lactis, Enterococcus faecalis and Candida spherica resulted the most abundant species. The results obtained from the analyses of this type of cheese allowed to evaluate the behaviour of lactic and non lactic microflora and to determine the predominant mesophilic lactic microflora.
Caratterizzazione microbiologica di formaggio artigianale prodotto da latte crudo di pecore di razza massese
PEDONESE, FRANCESCA;NUVOLONI, ROBERTA;D'ASCENZI, CARLO;INNOCENTI, ELENA;CERRI, DOMENICO;RINDI, SALVO
2000-01-01
Abstract
Microbiological characterization of an artisanal cheese produced from raw milk of Massese sheep was carried out in order to standardize the production. The research was conducted during 3 traditional cheesemaking processes. Samples from milk, rennet, curd and cheese at different stages of ripening (2, 7, 14, 28, 42 days) were analysed to determine the enumeration of: total mesophilic bacteria; lactococci; mesophilic lactobacilli; enterococci; yeasts and moulds; staphylococci and micrococci; total and faecal coliforms and Escherichia coli. Lactic acid bacteria remarkably increased during ripening: a very high level of lactococci was detected particularly during the first 14 days and was followed by a gradual decrease. Lactobacilli showed high levels, but lower than lactococci, during the whole ripening period. Enterococci and yeasts resulted quantitatively less important. Staphylococci and coliforms markedly decreased during ripening. Samples from rennet constantly revealed low bacterial counts. Means and standard deviations were calculated. ANOVA tables were constructed on data previously transformed according to Bartlett method. Isolation and identification of lactic acid bacteria and yeasts from the examined cheese were also carried out. 28 lactobacilli, 9 lactococci, 27 enterococci and 59 yeasts were identified. Lactobacillus plantarum, Lactococcus lactis subsp. lactis, Enterococcus faecalis and Candida spherica resulted the most abundant species. The results obtained from the analyses of this type of cheese allowed to evaluate the behaviour of lactic and non lactic microflora and to determine the predominant mesophilic lactic microflora.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
