Caracterização do fermento endógeno utilizado na fabricação do queijo Canastra no município de Medeiros, Minas Gerais, com ênfase em leveduras

• Autor(a) principal: Nóbrega, Juliana Escarião da
• Data de Publicação: 2007
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2823
• topic: Queijo artesanal; Bactérias láticas; Leveduras; Manufactured cheese; Bacteria; Yeasts; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS

This work had the objective to determine physicochemical parameters and to characterize the microbiota present in the natural whey cultures used in the manufacture of the Canastra cheese. The Canastra cheese is produced in the region of the Canastra Mountain range, Minas Gerais State, artisan made from raw cow s milk, and uses, as a culture starter, natural starters, prepared from the whey. The samples were collected in 8 properties, in the rain period, and in the dry period. The results demonstrated that the values of acidity and pH did not suffer alteration (P>0,05) in the two sampled periods. The average acidity found was 0,56 % and 0,66 %, in the raining period and in dry period, respectively. The pH presented an average of 5,02 in the raining period, and of 5,07 in the dry period. The NaCl index was superior (P<0,05) in the raining period, and it presented average of 7,39 %, while in the dry period, the average was of 4,13 %. The total counting of mesophile bacteria was smaller (P<0,05) in the raining period, with average of 5,94 Log UFC.mL-1, in the dry period the average found was of 7,50 Log UFC.mL- 1.The total coliform countings, E. coli and S. aureus did not differ (P>0,05) in the two sampled periods, and the averages found were, respectively, 2,30 Log UFC.mL-1, 1,50 Log UFC/ mL and 1,92 Log UFC.mL-1 in the raining period, and 2,61 Log UFC.mL-1, 1,50 Log UFC.mL-1 and 1,72 Log UFC.mL-1 in the dry period. Listeria sp. was not detected in any sample. Salmonella sp. was detected in 1 of the samples analyzed during the raining period. Great figures in the lactic acid bacteria countings were observed, all the evaluated groups presented countings superior than 5 logarithmic cycles, 395 lineages were isolated, and are in identification process. The average of the yeasts counting was of 5,24 Log UFC.mL-1 in the raining period, and of 4,16 Log UFC.mL-1 in the dry period. The predominant yeasts species during the raining period were Debaryomyces hansenii, Torulaspora delbruekii and Kluyveromyces lactis and in the dry period, had predominantly the Kluyveromyces lactis, Torulaspora delbruekii and Kluyveromyces marxianus species. There was a similarity of 80,87 % in the results between the traditional method and the 20 API® C AUX kit, used for the yeasts identification. This work is the beginning of the understanding of the main physicochemical and microbial components of the natural whey cultures used in the manufacture of the Canastra cheese. Studies for a better understanding of these components, their variations and interactions, as well as their contribution for the Canastra cheese characteristics and quality must still be determined.