DSpace Communidade: Produção Técnico-científica nas áreas de Ciências Exatas e TecnológicasProdução Técnico-científica nas áreas de Ciências Exatas e Tecnológicashttps://locus.ufv.br//handle/123456789/97912024-03-29T00:38:23Z2024-03-29T00:38:23ZHunter color dimensions, sugar content and volatile compounds in pasteurized yellow passion fruit juice (Passiflora edulis var. flavicarpa) during storageSandi, DelcioChaves, José Benício PaesSousa, Antônio Carlos Gomes deParreiras, June Ferreira MaiaSilva, Marco Túlio Coelho daConstant, Patrícia Beltrão Lessahttps://locus.ufv.br//handle/123456789/295882022-08-08T18:41:18Z2004-06-01T00:00:00ZTítulo: Hunter color dimensions, sugar content and volatile compounds in pasteurized yellow passion fruit juice (Passiflora edulis var. flavicarpa) during storage
Autor(es): Sandi, Delcio; Chaves, José Benício Paes; Sousa, Antônio Carlos Gomes de; Parreiras, June Ferreira Maia; Silva, Marco Túlio Coelho da; Constant, Patrícia Beltrão Lessa
Abstract: Changes in Hunter L, a and b values, glucose, fructose and sucrose contents, concentration of four volatile compounds (ethyl butirate, ethyl caproate, hexyl butirate and hexyl caproate) and furfural, were studied in yellow passion fruit juice (Passiflora edulis var. flavicarpa) pasteurized at 75ºC/60s, 80ºC/41s or 85ºC/27s, during storage at room temperature (25±5ºC) and refrigeration (5±1ºC) for 120 days. While the sucrose content decreased, the glucose and fructose contents increased significantly over storage time. The Hunter L and b values behaved similarly, with a tendency to decrease over time, inversely to Hunter a value. Volatile compound concentrations also decreased over time, inversely to the furfural content. Pasteurization at 85ºC/27s resulted minimum changes in the studied passion fruit characteristics, while that at 75ºC/60s was the most harmful. Storage under refrigeration tended to keep the best quality characteristics of the juice.; Foi estudada a variação dos valores "L", "a" e "b" do sistema de Hunter, dos teores de glucose, frutose e sacarose, e da concentração de quatro compostos voláteis (butirato de etila, caproato de etila, butirato de hexila e caproato de hexila) e furfural, em suco de maracujá-amarelo (Passiflora edulis var. flavicarpa) submetido à pasteurização (75ºC/60 s, 80ºC/41 s e 85ºC/27 s), durante o armazenamento a temperatura ambiente (25±5ºC) e refrigerada (5±1ºC) por 120 dias. Enquanto os teores de sacarose diminuíram, aqueles de glucose e frutose aumentaram significativamente. Os valores "L" e "b" apresentaram comportamento semelhante, com tendência a diminuir ao longo do tempo, inversamente ao valor "a". As concentrações dos compostos voláteis também diminuíram, exceto para o furfural. A pasteurização a 85ºC/27 s proporcionou as menores alterações nas características estudadas, enquanto aquela à 75ºC/60 s foi a mais prejudicial. O armazenamento sob refrigeração apresentou melhor tendência na manutenção das características.
Tipo: Artigo2004-06-01T00:00:00ZMicrobiological air quality of processing areas in a dairy plant as evaluated by the sedimentation technique and a one-stage air samplerSalustiano, Valéria CostaAndrade, Nélio JoséBrandão, Sebastião César CardosoAzeredo, Raquel Monteiro CordeiroLima, Sandra Aparecida Kitakawahttps://locus.ufv.br//handle/123456789/295852022-08-08T18:25:58Z2003-07-01T00:00:00ZTítulo: Microbiological air quality of processing areas in a dairy plant as evaluated by the sedimentation technique and a one-stage air sampler
Autor(es): Salustiano, Valéria Costa; Andrade, Nélio José; Brandão, Sebastião César Cardoso; Azeredo, Raquel Monteiro Cordeiro; Lima, Sandra Aparecida Kitakawa
Abstract: The microbiological air quality at processing areas in a dairy plant was evaluated by using a one-stage air sampler, based on Andersen principles (impaction technique) and by culture settling plate technique, also known as sedimentation technique. Among these areas, milk reception, packaging, and pasteurization rooms were included. Rooms where cheese, yogurt, butter and "doce de leite"(Latin American typical treat made of concentrated milk and sugar) are made were also evaluated. For all processing areas, the numbers of mesophilic aerobic bacteria and yeast and molds recovered by air sampler were higher than 90 CFU·m-3 – the maximum value recommended by American Public Health Association (APHA). In four of the six processing areas, the microbial numbers were higher than APHA's standard (30 CFU.cm-2.week-1) according to culture settling plate technique. The results showed a difference (p<0.05) for the Staphylococcus aureus numbers (from <1.0 to 4.3 UFC·m-3) at processing areas. The numbers of microorganisms recovered by impaction technique were about 2 to 10 times higher than by sedimentation technique. The microorganism group determined at processing areas depended mainly on the technique. By the air sampler technique, it was observed the predominance of yeasts and molds and by sedimentation technique, of mesophilic aerobic bacteria. The increase of temperature at processing areas did not seem to affect the numbers of airborne microorganisms. On the other hand, the increase of air humidity showed a relation with the increase of microorganism numbers. The impaction technique should be chosen since it is better to recover airborne microorganisms, including pathogens.; Foi avaliada a microbiota do ar dos ambientes de recepção, embalagem e pasteurização de leite, produção de queijos, de iogurte e de doce de leite e manteiga em uma indústria de laticínios pelas técnicas de sedimentação e de impressão em ágar utilizando um amostrador de ar de um estágio baseado no princípio de Andersen. As contagens de microrganismos mesófilos aeróbios e de fungos filamentosos e leveduras pela técnica impressão em ágar ultrapassaram 90UFC·m-3 de ar, valor máximo recomendado pela APHA. Pela técnica de sedimentação, as contagens microbianas do ar de quatro ambientes também ultrapassaram 30UFC·cm-2·semana-1, conforme recomendação da APHA. Os ambientes diferiram (p<0,05) apenas para os números de Staphylococcus aureus. (<1,0 a 4,3 UFC.m-3). As contagens microbianas por impressão em ágar foram de 2 a 10 vezes maiores que as obtidas por sedimentação, evidenciando a maior capacidade da impressão em ágar em determinar microrganismos do ar, inclusive patógenos. Quanto à distribuição da microbiota do ar, houve a predominância de fungos filamentosos e leveduras pela técnica de sedimentação em ágar e de mesófilos aeróbios pela de impressão em ágar. O aumento da temperatura ambiente, ao contrário do aumento da umidade relativa do ar, não contribuiu para maiores contagens microbianas no ar.
Tipo: Artigo2003-07-01T00:00:00ZDLLME-GC/ECD Method for the Residual Analysis of Parathion-Methyl and its Application in the Study of the UV-Photodegradation ProcessPimenta, Gustavo G.Queiroz, Maria E. L. R. deVictor, Raquel P. D.Noronha, Luiz M.Neves, Antônio A.Oliveira, André F. deHeleno, Fernanda F.https://locus.ufv.br//handle/123456789/295842022-08-08T18:25:43Z2017-11-01T00:00:00ZTítulo: DLLME-GC/ECD Method for the Residual Analysis of Parathion-Methyl and its Application in the Study of the UV-Photodegradation Process
Autor(es): Pimenta, Gustavo G.; Queiroz, Maria E. L. R. de; Victor, Raquel P. D.; Noronha, Luiz M.; Neves, Antônio A.; Oliveira, André F. de; Heleno, Fernanda F.
Abstract: A new method has been developed to determine trace levels of organophosphorus pesticide parathion-methyl in water samples by using dispersive liquid-liquid microextraction (DLLME), followed by gas chromatograph coupled with electron capture detector (GC/ECD) analysis. The optimized and validated method showed high extraction recovery (101.1%), high enrichment factor (57.3), low limits of detection and quantification, 0.083 and 0.250 µg L-1, respectively. The established DLLME-GC/ECD method has been successfully applied for the evaluation of the photodegradation of the parathion-methyl by UV254nm radiation in different conditions of pH and temperature. The parathion-methyl photodegradation at pH 3 and 35 °C achieved > 99.5% after 120 min of exposition. For this condition, it was observed the kinetic rate of 0.0515 min-1, the quantum yield of 1.22 × 10-5 mol Einstein-1 and a half-life time of 13.46 min. All experimental conditions tested proved to be strongly influenced by pH and temperature. The application of the optimized process in distilled and drinking water spiked with parathion-methyl provided residues of this pesticide at levels below the maximum permitted by Brazilian legislation, which is 9.0 µg L-1.
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Tipo: Artigo2017-11-01T00:00:00ZMultivariate calibration to determine phorbol esters in seeds of Jatropha curcas l. Using near infrared and ultraviolet spectroscopiesRoque, Jussara V.Dias, Luiz A. S.Teófilo, Reinaldo F.https://locus.ufv.br//handle/123456789/295832022-08-08T18:25:33Z2017-08-01T00:00:00ZTítulo: Multivariate calibration to determine phorbol esters in seeds of Jatropha curcas l. Using near infrared and ultraviolet spectroscopies
Autor(es): Roque, Jussara V.; Dias, Luiz A. S.; Teófilo, Reinaldo F.
Abstract: The building of partial least squares (PLS) regression models using near infrared (NIR) and ultraviolet (UV) spectroscopies to estimate the concentrations of phorbol esters (PEs) in Jatropha curcas L. is presented. The models were built using two algorithms for variable selection, ordered predictors selection (OPS) and genetic algorithm (GA). Chromatographic analyses were performed to determine the concentrations of PEs. Spectral data were obtained from seeds and oil extract. The results of PLS models were performed by analyzing statistical parameters of quality such as root mean square error of prediction (RMSEP) and correlation coefficient of external predictions (Rp). The parameters obtained for NIR-PLS and UV-PLS models with OPS were respectively: RMSEP 0.48 and 0.22 mg g-1 and Rp 0.49 and 0.96. For GA were obtained, respectively: RMSEP 0.52 and 0.28 mg g-1 and Rp 0.12 and 0.95. The models built from seeds and oil extracts can be used respectively for screening and to accurately predict the PEs content. The OPS method provided simpler and more predictive models compared to those obtained by the selection of variables using the GA. Thus, the UV-PLS-OPS model can be used as an alternative method to quantification of PEs.
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Tipo: Artigo2017-08-01T00:00:00Z