Biodiversidade microbiana, descritores físico-químicos e sensoriais dos queijos artesanais fabricados nas regiões da Serra da Canastra e do Serro, Minas Gerais

• Ano de defesa: 2012
• Autor(a) principal: Nóbrega, Juliana Escarião da
• Orientador(a): Ferreira, Célia Lúcia de Luces Fortes
• Banca de defesa: Cunha, Luciana Rodrigues da , Pinto, Uelinton Manoel
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Ciência e Tecnologia de Alimentos
• Departamento: Ciência de Alimentos; Tecnologia de Alimentos; Engenharia de Alimentos
• País: BR
• Palavras-chave em Português: Físico-química; Microbiologia; Queijo artesanal
• Palavras-chave em Inglês: Physicochemical; Microbiology; Artisanal cheese
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS
• Link de acesso: http://locus.ufv.br/handle/123456789/457

The objective of this study was to characterize artisanal cheeses produced in the Serra da Canastra and Serro regions. We evaluated their physical, visual and physicochemical properties. We quantified the main groups of lactic bacteria and isolated 271 clones from the M17 medium, incubated at the temperature of 24oC/3days. The biodiversity of the Enterococcus faecalis was investigated by PFGE. The microbial diversity was also studied by TTGE, un culture-independent method. The sensory profiles of Canasta and Serro cheeses were determined by means of quantitative descriptive analysis. Cocci and mesophilic lactobacilli formed the dominant microbiota in Canasta and Serro cheeses during the rainy and dry seasons. The biodiversity of these products, accessed by TTGE, indicated that the Canastra cheese had the greatest diversity and it had a total of 10 different bands, 3 of them found in all of the evaluated cheeses. In the TTGE profile of the Serro cheese, 8 different bands were found, 1 of them was present in all evaluated samples. The results of the identification of the 271 isolates in M17 medium confirm the results of the TTGE and indicate a greater diversity of species in the Canastra cheese. The species of Lactobacillus plantarum, Streptococcus gallolyticus, Streptococcus infantarius subsp. infantarius, Lactococcus lactis subsp. lactis, Enterococcus faecalis and Leuconostoc fallax were the most frequent in Canastra cheese, while the species of Lactobacillus plantarum, Streptococcus salivarius, Lactococcus lactis subsp. lactis and Enterococcus faecalis were the most common in Serro cheese. Seventeen PFGE profiles were identified among the isolates of Enterococcus faecalis, and the identified strains were specific to the farm where the cheese was made. The Canastra and Serro cheeses are characterized by cylindrical shape, without bulging on the surface and side, and uniform distribution of little eyelet holes of mechanical kind in Canastra cheese and mechanical and microbial kind in Serro cheese. The Serro cheeses had higher acidity and moisture level than the Canastra cheeses. We selected 16 attributes for the sensory characterization of the two cheeses: skin color; skin color uniformity; surface roughness; mass color; buttery, curd, barnyard and rancid aroma; elasticity; hardness; friability; stickiness; salty, bitter and sour taste; and spicy flavor. Evaluating the averages of Canasta and Serro cheeses data, they differed in 11 attributes, but the ones that best differentiated and distinguished them were: skin color, barnyard and rancid aroma, and sour taste.