Microfiltração como alternativa na produção de queijos com olhaduras e utilização da fase aquosa para avaliação de suas características físico-químicas

• Ano de defesa: 2011
• Autor(a) principal: Dias, Geruza
• Orientador(a): Furtado, Mauro Mansur
• Banca de defesa: Martins, José Manoel , Fariña, Luciana Oliveira de
• 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: Microfiltração; Esporulados; Estufamento
• Palavras-chave em Inglês: Microfiltration; Sporulated; Stuffing
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::TECNOLOGIA DE ALIMENTOS
• Link de acesso: http://locus.ufv.br/handle/123456789/450

The production of cheeses with eyes has been increasing in Brazil and one of the main problems is the occurrence of late blowing. To study this problem, cheeses with eyes were produced from microfiltered milk in order to eliminate common contaminating microorganisms and spores of Clostridium. Cheese physiochemical, microbiological and sensorial characteristics were evaluated. Since the aqueous phase accumulates hydrosoluble products resulting from bacterial metabolism and enzymatic reactions, the same physiochemical characteristics were evaluated in that phase and in the cheese, as well. The role of NSLAB Lactobacillus rhamnosus and Enterococcus durans in the flavor development and in the texture of the cheese made from microfiltered milk was also verified. The milk was microfiltered in a tubular cylindrical membrane with 120l/h flow and 1.4&#956;m pore size. In all treatments. Propionibacterium freudenreichii and starter cultures Lactobacillus helveticus, S. thermophilus, Lactococcus lactis subsp lactis and Lactococcus lactis subsp cremoris were added. The experiment consisted of four treatments: cheeses with eyes from pasteurized milk (P); cheeses with eyes from pasteurized milk added with NSLAB culture (PC); cheeses with eyes from microfiltrated milk (M) and cheeses with eyes from microfiltrated milk added with NSLAB culture (MC). Physiochemical and microbiological analyses were accomplished in milk and cheese. In the aqueous phase only physiochemical analyses were carried out. The physiochemical analyses in cheeses and aqueous phase were accomplished at four ripening phases, such as 2, 15, 45 and 60 days. The acceptance test was performed at 60 days of ripening. The analytical results for moisture, dry matter, sodium chloride, ashes, protein, nonprotein nitrogen and noncaseinic nitrogen obtained in the aqueous phase and in the cheeses differed (P <0.05) for ripening time, but did not differ (P <0,05) among treatments. Among the analyzed organic acids, only butyric acid contents in aqueous phase and in the cheeses manufactured with microfiltered milk showed differences (P <0.05) compared to results from cheeses manufactured with pasteurized milk, indicating that microfiltration was efficient in eliminating milk deteriorating microorganisms, including spores of Clostrídium spp. which are responsible for the production of butyric acid. All cheeses presented absence of Listeria monocytogenes and Salmonella sp. and 30 and 45°C coliform groups and S. aureus stayed within the maximum limits of the current legislation. Concerning flavor assessment, the sensorial analysis demonstrated that the MC treatment obtained the highest average (P <0.05), as being between I liked moderately and I liked very much , and the PC treatment obtained the second higher score, therefore not differing (P>0.05) from the treatments P and M. Concerning texture development, the treatment P obtained the highest average, as being between I liked moderately and I liked very much , differing (P <0.05) from treatment M. The treatments M and MC did not differ between themselves (P>0.05). Concerning the global feeling, no influence occurred (P>0.05) among treatments. Cheeses made in this experiment were the first ones elaborated with this technology in the country. The promising results obtained will motivate the industries to use this technology for the elaboration of long-ripened cheeses keeping their original characteristics as well as significantly reducing losses caused by the use of the pasteurized milk, which does not eliminate the presence of the Clostridium spp.