Potencial de aminas bioativas como indicadoras do estádio de maturação e o papel da microbiota endógena do leite cru na inocuidade e características do queijo Minas artesanal

• Autor(a) principal: Araújo, Tatiane Ferreira
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/484
• topic: Queijo artesanal; Aminas biogênicas; Segurança alimentar; Bactérias láticas; Enterobacteriaceae; Artisan cheese; Biogenic amines, Food security; Lactic acid bacteria, Enterobacteriaceae; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS

The Minas artisanal cheese (QMA) is recognized for its unique sensory characteristics. Made in five regions already characterized (Araxá, Cerrado, Campo das Vertentes, Canastra and Serro), the QMA has two manufacturing technologies differentiated by the type of press: only with the pressure of hands (Serro) and manual pressing with the use of a tissue (Araxá, Cerrado, Campo das Vertentes and Canastra). This difference is the basis of the definition of the two minimum periods of ripening presently used for cheese of Serro (17 days) and Canastra (22 days). These minimum periods of ripening were defined based on the permanence of the micro-organism Staplylococcus aureus during the ripening until the limit established by the legislation (2 log CFU g -1). However, most production is offered for sale the QMA period less than the currently set by law. Is known that endogenous microbiota in milk through of ripening contributes to the safety of the product. It was also found by means of pre-experiments in this study different bioactive amines (AB) are accumulated along the ripening of the QMA. Thus, the research aimed to: a) evaluate the role of endogenous microbiota in raw milk safety of QMA b) Verify the potential of AB in the indication of the ripening period of the QMA. To assess the safety related phenomenon inferred by ripening was used as a model QMA Serro. Evaluated over 60 days of aging (8, 17, 30 and 60 days) in QMA made with raw milk (NP) and pasteurized (P) physico chemical parameters (pH, titratable acidity, chloride, fat, activity water, ash, total nitrogen), extended depth of proteolysis; profile of organic acids and bioactive amines, microbiological parameters (colony forming units of Lactococcus, Lactobacillus, Enterococcus, aerobic mesophilic, molds and yeasts, Enterobacteriaceae, coliforms at 30oC and 45 ° C; Staplylococcus aureus and sensory parameters (texture and color). the results showed differences (P <0,05) in pH, titratable acidity, fat, fat in dry matter (GES), moisture and total nitrogen. The more intense proteolysis in cheese made with raw milk affect the texture and color of the mass of the cheeses (P < 0,05) making it possible to establish a correlation with the stage of maturation. The heat treatment may have altered the endogenous microbiota qualitatively since the concentrations evaluated microbial groups did not differ with the xiii exception of S. aureus counts remained higher (20 and 35 days respectively for cheeses made with raw milk and pasteurized) to which the legislation today. This finding corroborates the role of endogenous microflora in the safety of the QMA made with raw milk. The heat treatment affected the microbiota altered the profile of organic acids (lactic, citric, butyric, propionic and acetic acid) and bioactive amines. There is the potential of bioactive amine histamine as an indicator of ripening stages. Suggest a range between 8.65 to 9.29 mg/100 g of histamine in QMA to Serro with 17 days of ripening, made from raw milk. Besides compromising safety inferred by the heat treatment of milk, it was also found that the texture and color were changed in QMA Serro made with pasteurized milk when compared to traditional product made with raw milk. Suggested that further studies be conducted to identify the microbial species that predominate in cheese made with raw milk and are eliminated by heat treatment, for a better understanding of the phenomenon that has secured a matured product safe for consumption.