Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos - PPGCTA/ITEC

URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/8900

O Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos (PPGCTA) integra o Instituto de Tecnologia (ITEC) da Universidade Federal do Pará (UFPA) e iniciou suas atividades em 2004 com o curso de Mestrado Acadêmico em Ciência e Tecnologia de Alimentos. Em 2010, a CAPES aprovou o Doutorado, que teve início em 2011.

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Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Desenvolvimento de métodos por CL-EM/Em e ocorrência de antimicrobianos em peixes de aquicultura
(Universidade Federal do Pará, 2016-11-22) GUIDI, Letícia Rocha; GLÓRIA, Maria Beatriz de Abreu; http://lattes.cnpq.br/6895373188728113; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170
The consumption of fish has increased in recent years in Brazil, especially due to the announcement that their intake can bring numerous health benefits and also due to its high nutritional value (high biological value protein, high content of omega-3 fatty acids). The quality, safety and security of farmed fish for human consumption are therefore a public health issue and must be monitored. In Brazil, there is a lack of information regarding the use of antimicrobials in aquaculture. Although only two antibiotics are allowed for use in aquaculture in Brazil, there is a wide variety of antibiotics that may be used illegally or can reach the fish due to environmental contaminations, mainly of water. The objective of this study was to develop multiresidue methods of analysis of antibiotics in fish muscle and to evaluate the quality of fish from Minas Gerais and Pará with respect to the presence of antibiotic residues. In addition, an extensive literature review was conducted with respect to existing methods of analysis and the occurrence of chloramphenicol (banned antibiotic) and amphenicols in food. A LC-MS/MS screening method was validated for the analysis of 40 antibiotics of six different classes (aminoglycosides, beta-lactams, macrolides, quinolones, sulfonamides and tetracyclines) in fish muscle. Only 15% of the samples (n=29) were positive for enrofloxacin. A quantitative LC-MS/MS method of analysis of quinolones and tetracyclines in fish muscle was also optimized and validated. The precision, in terms of the relative standard deviation, was under 20% for all of the compounds, and the recoveries were between 89.3% and 103.7%. CCα varied from 17.87 to 323.20 μg.kg-1 and CCβ varied from 20.75 to 346.40 μg.kg-1. In general, real samples showed good quality relative to the presence of antibiotic residues. All 29 positive samples for enrofloxacin contained levels below the Maximum Residue Limit allowed by Brazilian legislation (100 μg.kg-1).
Acesso aberto (Open Access)
Estruturas supramoleculares de α-lactoalbumina e glicomacropeptídeo: produção, caracterização, propriedades funcionais e carreamento de vitamina B2 e quercetina
(Universidade Federal do Pará, 2016-03-01) DINIZ, Renata Silva; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170
This study aimed to produce, characterize and verify the technical and functional properties of α-lactalbumin (α-la) and glycomacropeptide (GMP) supramolecular structures, and their potential in the food industry. The α-la/GMP supramolecular structures were prepared in a molar ratio of 1: 0.689, respectively. This proportion was defined by isothermal titration calorimetry and differential scanning calorimetry aided in determining the temperature values used since the formation of supramolecular structures was verified at higher and lower values than the denaturation temperature of the α-la. For GMP could not be established denaturation temperature, because it has no defined tertiary structure. The circular dichroism and fluorimetry analysis showed that there was interaction between α-la and GMP molecules. The supramolecular structures, in general, kept the α-helix secondary structures, but the intensity of these secondary structures may vary in the different conditions tested. The supramolecular structures have hydrophobic core. The particle size of supramolecular structures ranging from nano to micrometer, demonstrating that can be controlled through variables tested: pH (3.5 to 6.5) Heating temperature (25 to 75 °C) and heating time. The stability of supramolecular structures was evaluated by monitoring the particle size and the ζ potential at temperatures of 4 and 25 °C for 60 days. The supramolecular structures formed at pH 6.5 have higher system stability with ζ potential absolute values of approximately -30 mV. The morphology of supramolecular structures was determined by transmission electron microscopy and it was observed that proteins associated forming spherical structures. The foaming ability of supramolecular structures was evaluated by homogenization method, determining the increased volume, stability and expansion of the foam. It was found that the structures formed at pH 6.5 and 75 °C showed higher foaming ability. The emulsifying properties of the supramolecular structures were determined by the emulsifying activity index and emulsion stability index, using the turbidimetric method. However, the variables tested (pH, temperature and time) showed no effect on emulsifying properties. The surface tension of the supramolecular structures, determined by the Wilhelmy method showed a mean value of 50.825 mNm-1, demonstrating that the supramolecular structures can be effective in stabilizing emulsions and foam products. The supramolecular structures were able to encapsulate quercetin and vitamin B2, with maximum encapsulation efficiency of 98.64% and 31.11%, respectively. The stability of carrier systems was evaluated by monitoring the particle size and ζ potential for 60 days. For quercetin, systems prepared at pH 6.5 were stable for 60 days, while for vitamin B2, the stability of 60 days was demonstrated by the systems prepared at pH 3.5.

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Navegando Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos - PPGCTA/ITEC por CNPq "CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::CIENCIA DE ALIMENTOS"