Detalhes bibliográficos
Ano de defesa: |
2013 |
Autor(a) principal: |
Costa, Silvânio Silvério Lopes da
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Orientador(a): |
Araújo, Rennan Geovanny Oliveira
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Banca de defesa: |
Não Informado pela instituição |
Tipo de documento: |
Dissertação
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Tipo de acesso: |
Acesso aberto |
Idioma: |
por |
Instituição de defesa: |
Não Informado pela instituição
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Programa de Pós-Graduação: |
Pós-Graduação em Química
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Departamento: |
Não Informado pela instituição
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País: |
Não Informado pela instituição
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Palavras-chave em Português: |
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Palavras-chave em Inglês: |
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Área do conhecimento CNPq: |
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Link de acesso: |
https://ri.ufs.br/handle/riufs/6082
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Resumo: |
The pet food industry for dogs and cats has grown extensively. This growth has been reflected from the requirements of the owners of these animals by products with different characteristics and which are suitable nutritional quality, according to the need of the animal. Therefore, we emphasize the importance in determining the mineral composition of these foods, especially in the sense of possible contaminants. In this work, a method proposed for determination of mineral composition (S, Al, Ca, Cu, K, Mg, Mn, P, Zn, Sr, V, Fe, Ni, Cr and Ba) in dog and cat foods by inductively coupled plasma optical emission spectrometry (ICP-OES). The samples were digested by microwave-assisted digestion method using dilute HNO3 (2.0 mol L-1) and H2O2 (6% m/v). The ratio of the reagents used in digestion was established by a full-two level factorial design. The optimum conditions for RF power was 1.2 kW and nebulization gas flow rate of 1.0 L min-1, which were established by a 32 factorial design with two variables, evaluating these conditions the methodology of response surface analysis. To evaluate the precision and accuracy of the proposed method, five certified reference materials (CRM) were analyzed: wheat flour (NIST 1567a), bovine liver (NIST 1547), peach leaves (NBS 1577), oyster tissue (NIST 1566b) and fish proteins (DORM-3). The analysis of the CRM has shown that the values are in agreement with the certified values ranged between 80 (Cr) and 117% (Cd), with relative standard deviations (% RSD) lower than 5%, except for Ni and Cr which exceeded 15%. The limits of quantification (LOQ) were obtained between 0.075 (Ba, 233.527 nm) and 87 ìg g-1 (Ca, 373.690 nm). The method was applied to analysis of 17 cat food samples with concentrations varying between 2.3 mg kg-1 for Ba and 2.8 g kg-1 for Ca and 24 of dog food samples ranging between 3.8 mg kg-1 for Cu and 3.4 g kg-1 for Ca collected in supermarkets of cities the of State of Sergipe, Brazil. The exploratory techniques of data using hierarchical cluster analysis (HCA) and principal components analysis (PCA), can conclude that the ration for the pet foods were uniform, since there was no trend in the formation of distinct groups for possible rating, according to their mineral composition, except the brand "F2", which clustered with the presence of concentrations of aluminum and copper in feed composition for dog. |