| Abstrakt: |
Secondary microflora in three batches of Idiazabal cheese were studied. In one of them the milk was cold-stored for 3 d and showed lower counts, except for psychrotrophs, Enterobacte-riaceae, Clostridium tyrobutyricum and moulds. Significant differences in NaCl, dry matter and pH in raw milk were observed. Aerobic mesophilic, psychrotrophic flora and Enterococcus increased during coagulation, pressing and brining, while the rest of the secondary microflora was inhibited. During ripening, Enterobacteriaceae and Micrococcaceae declined in the first 2 ripening months; the Enterococcus were stable, except in the cheese from milk cold-stored for 3 d, for which they presented low counts and Clostridium tyrobutyricum, yeast and moulds showed an irregular evolution. ? Inra / Elsevier, Paris.La microflore secondaire de trois lots de fromage idiazabal a ?t? ?tudi?e. Le lot fabriqu? avec du lait r?frig?r? pendant 3 j a pr?sent? les d?nombrements les plus bas, sauf les bact?ries a?robies psychrotrophes, Enterobacteriaceae, Clostridium tyrobutyricum et les moisissures. Des diff?rences significatives dans le lait cru ont ?t? observ?es en fonction des param?tres : chlorure de sodium, extrait sec et pH. La flore a?robie mesophile, a?robie psychrotrophe et les enterocoques ont augment? pendant les phases de coagulation, pressage et salage, tandis que les autres microflores secondaires ont ?t? inhib?es. Le niveau des Enterobacteriaceae et des Micrococcaceae a chut? pendant les deux premiers mois d'affinage ; Enterococcus est stable (environ 6 log ufc-g-1), ? l'exception des fromages fabriqu?s ? partir du lait r?frig?r? pendant 3 j, o? ce groupe microbien a pr?sent? des d?nombrements inf?rieurs ? 5 log ufc-g-1. Clostridium tyrobutyricum, les levures et les moisissures ont montr? une ?volution irr?guli?re. ? Inra / Elsevier, Paris. |
