14 research outputs found

    Soil management practices: chemical and spectroscopic characterization

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    The aim of this study was to evaluated the facility to apply spectroscopic analysis coupled with chemometrics analysis as a rapid method for soil analysis. Soil samples from different depths (0-10, 10-20 and 20-30 cm) and treatment sites (area of fallow land for 5 years, area of no-tillage for 10 years and native forest) were applied in this study. Soil chemical characterization based on the concentration of macro-, micronutrients and the level of the toxic element showed significant different among to the samples under differences management systems. PCA and HCA analysis evaluated with soil chemical characterization showed that the samples were grouped according to the management systems. Similar results were obtained in the PCA and HCA analysis developed with FTIR spectra. The results support the application of FTIR to evaluate the quality of soil providing a simple, rapid, and nondestructive method for the soil science.The aim of this study was to evaluate the possibility to apply chemical and spectroscopic analysis, coupled with chemometric tools, as a rapid method for soil characterization. Soil samples from different depths (0-10, 10-20 and 20-30 cm) and sites (fallow area for 5 years, area of no-tillage for 10 years and native forest) were applied in this study. Soil chemical characterization based on the concentration of macronutrients (P, K Ca, and Mg), micronutrients (Mn, Fe, Zn, and Cu), the level of aluminum, pH, organic matter (OM) and humification degree. For spectroscopic characterization, only the humic acid (HA) fraction was analyzed in the mid infrared spectrometer. Principal Components Analysis (PCA) and Hierarchical Clustering Analysis (HCA) showed clusters based on the management systems. These results support the application of chemometric toolls to evaluate the quality of soil providing a simple and rapid method for the soil science

    Technological characteristics of fish species with creating potential in Paraná southwest region

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    The fish meat has a particular chemical composition which gives its high nutritional value. However, this food is identified for being highly perishable and this aspect is often named as a barrier to fish consumption. The southwestern Paraná region, parallel to the country's reality, it is characterized by low fish consumption; and one of the strategies aimed at increasing the consumption of this important protein source is encouraging the production of other species besides tilapia. Within this context, it is necessary to know about the meat characteristics. In this sense, the objective of this study was to evaluate the technological potential of pacu, grass carp and catfish species. To do so, at first, it was discussed the chemical and biometric assessment under two distinct descriptive statistical methods, of the three species; and it was also evaluated the discriminating capacity of the study. In a second moment, an evaluation of effects done by two different processes of washing (acid and alkaline) regarding the removal of nitrogen compounds, pigments and the emulsifying ability of the proteins contained in the protein base obtained. Finally, in the third phase, it was aimed to realize the methodology optimization in GC-MS for the analysis geosmin and MIB (2-metilisoborneol) compounds that are responsible for taste/smell of soil and mold in freshwater fish. The results showed a high protein and low lipid content for the three species. The comparison between means and medians revealed symmetry only for protein values and biometric measurements. Lipids, when evaluated only by the means, overestimate the levels for all species. Correlations between body measurements and fillet yield had low correlation, regardless of the species analyzed, and the best prediction equation relates the total weight and fillet weight. The biometric variables were the best discriminating among the species. The evaluation of the washings, it was found that the acidic and basic processes were equally (p ≥ 0.05) efficient (p ≤ 0.05) for the removal of nitrogen compounds on the fish pulps. Regarding the extraction of pigments, a removal efficiency was recorded only for the pacu species, the data were assessed by the parameters L *, a *, b *. When evaluated by the total color difference (ΔE) before and after washing for both processes (acid/alkaline) the ΔE proved feasible perceived by naked eye for all species. The catfish was characterized as the fish that presents the clearest meat with the basic washing considered the most effective in removing pigments for this species. Protein bases obtained by alkaline washes have higher emulsifying capacity (p ≤ 0.05) when compared to unwashed and washed in acid process pulps. The methodology applied for the quantification of MIB and geosmin, allowed to establish that the method of extraction and purification of analytes had low recovery and future studies should be developed for identification and quantification of MIB and geosmin on fish samples.CNPq; CAPESA carne de pescado possui composição química particular que lhe confere elevado valor nutricional. Entretanto, esse alimento é identificado pela alta perecibilidade, aspecto esse muitas vezes apontado como barreira ao consumo de pescado. A região Sudoeste do Paraná, paralela à realidade do país, é caracterizada pelo baixo consumo de pescado; e uma das estratégias apontadas para o aumento do consumo dessa importante fonte proteica é o incentivo à produção de outras espécies além da tilápia. Dentro desse contexto, faz-se necessário o conhecimento a respeito das características da carne de pescado. Nesse sentido, o objetivo do presente trabalho foi avaliar o potencial tecnológico das espécies pacu, carpa capim e catfish. Em um primeiro momento realizou-se a avaliação química, frescor e biométrica, sob dois métodos estatísticos descritivos distintos, das três espécies; e avaliou-se a capacidade discriminante das variáveis em estudo. Em um segundo momento buscou-se avaliar os efeitos de dois processos distintos de lavagem (ácida e alcalina) no que diz respeito à remoção de nitrogenados e pigmentos e na capacidade emulsificante das proteínas da base proteica obtida. A terceira fase deste trabalho objetivou-se otimizar a metodologia em CG-EM para análise de compostos geosmina e MIB (2-metilisoborneol), compostos esses responsáveis pelo sabor/odor a terra e mofo em pescados de água doce. Os resultados revelaram altos teores de proteína e baixos teores de lipídios para as três espécies. A comparação entre médias e medianas revelaram simetria apenas para os valores de proteínas e medidas biométricas. Os lipídios quando avaliados apenas pelas médias superestimaram os teores para todas as espécies. Correlações entre medidas corporais e rendimento de filé apresentaram baixa relação, independente da espécie analisada, sendo a melhor equação de predição a que relaciona peso total e peso de filé. As variáveis biométricas foram as melhores discriminantes entre as espécies. Quanto à avaliação das lavagens, verificou-se que os processos ácido e básico foram igualmente (p ≥ 0,05) eficientes (p ≤ 0,05) na remoção dos compostos nitrogenados nas polpas de pescado. No que diz respeito à extração de pigmentos, eficiência de remoção foram registradas apenas para a espécie pacu, quando os dados foram avaliados pelos parâmetros L*, a*, b*. Quando avaliados pela diferença total de cor (ΔE) antes e após as lavagens, para ambos os processos (ácido/alcalino), os ΔE revelaram factível percepção a olho nu para todas as espécies. Catfish foi caracterizado como o pescado que apresenta a carne mais clara e a lavagem básica foi apontada como a mais eficiente para remoção de pigmentos para essa espécie. As bases proteicas obtidas pela lavagem alcalina apresentaram maior capacidade emulsificante (p ≤ 0,05) quando comparadas às polpas sem lavar e lavadas em processo ácido. A metodologia aplicada para quantificação de MIB e geosmina permitiu constatar que o método de extração e purificação dos analitos apresentou baixa recuperação e que estudos futuros devem ser desenvolvidos para identificação e quantificação de MIB e geosmina em amostras de pescado

    Projective mapping with food stickers: A good tool for better understanding perception of fish in children of different ages

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    The objective of this study was to better understand the perception of fish products among school children of three different age groups, 5–6 years, 7–8 years and 9–0 years. In order to do so, we used Projective Mapping (PM) with food stickers and a word association task (WA). A total of 149 children from three public schools in the state of Parana, Brazil, have participated on this study. The age groups were interviewed (on 1–1 basis) by six monitors qualified to apply the sensory methods used. Ten stickers with drawings of healthy foods (sushi, salad, fruit, fish, chicken), and less-healthy foods (pizza, flan, cake, hamburger, french fries) were given to the children. They were then asked to stick them on an A3 sheet, in a way that the products they considered similar should be positioned close to each other, and those they considered very different should be kept apart. Afterwards, they were asked to described the images and group of images (ultra flash profile). The PM was easily used and understood by all children, and the use of images may potentially have eased its application. Result analyses showed different perceptions from the different age groups. Hedonic perceptions in relation to fish products had a higher weight in the perceptual spaces of older children. WA technique proved to be an important tool to understand fish perception by children, and reinforced the results previously obtained by PM. These results may imply that there could be a window of opportunity in which younger children will be more open to eat fish.acceptedVersio

    Check all that apply (CATA) as an instrument for the development of fish products

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    Abstract The objective of this paper is to develop a fish-based product. Through the innovative sensorial check all that apply (CATA) technique, employed in two stages of the development of the product – market research and the sensorial and hedonistic characterization of the final product – the aim was to develop a fish by-product that could respond to the needs of the consumer market. Results showed that the CATA technique is an important instrument for researching the consumer market and indicated the kind of fish by-product to be developed and its desired features. Nugget was the resulting by-product. The second application of CATA made possible the sensorial description of the by-product as being crisp, with little fish odor, light in color, well-seasoned and tasty. Therefore, the CATA technique proved to be an important research instrument in the fish consumption market as well as a quick technique for the complete description of fish nuggets

    APPLICATION OF FOURIER TRANSFORM INFRARED SPECTROSCOPY, CHEMICAL AND CHEMOMETRICS ANALYSES TO THE CHARACTERIZATION OF AGRO-INDUSTRIAL WASTE

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    Agroindustrial waste in general presents significant levels of nutrients and organic matter and has therefore been frequently put to agricultural use. In this context, the objective of this study was to determine the chemical composition, nitrogen, phosphorus, potassium, calcium, magnesium and carbon content, as well as the qualitative characteristics through Fourier transform infrared spectroscopy of four samples of poultry litter and one sample of cattle manure, from the southwestern region of Paraná, Brazil. Results revealed that, in general, the poultry litter presented higher amount of nutrients and carbon than the cattle manure. The infrared spectra allowed identification of the functional groups present and the differences in degree of sample humification. The statistical treatment confirmed the quantitative and qualitative differences revealed

    Acceptance of fish hamburgers in school meals in the Southwest Region of Paraná, Brazil

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    <div><p>Abstract The regular consumption of fish provides health gains for people, and its introduction in school meals is an important strategy to insert the habit of consuming this food by a population. Thus the objective of this study was to verify the acceptance of fish, presented in the form of hamburger, by children in municipal primary schools in the town of Pato Branco, Brazil, in which the school cooks had been trained to produce fish hamburgers. Acceptance was evaluated using a hedonic scale with 5 facial classifications (1 = disliked extremely to 5 = liked extremely). Students of both genders from 5 to 10 years of age (n = 142) were served the hamburgers for their midday meal, representing the protein portion of the meal. The results were analyzed by logistic regression. No effect of age or gender was observed between the children in the acceptance of the hamburgers, but the interaction between age and gender was significant. The cluster analysis was applied to distinguish this interaction using two-way joining to present the results, which showed the effect between specific age and gender situations. The acceptance index was 87% showing the potential for the consumption of this food by children.</p></div

    Rotatividade na força de trabalho da rede municipal de saúde de Belo Horizonte, Minas Gerais: um estudo de caso Workforce turnover rates in the municipal health network in Belo Horizonte, Minas Gerais: a case study

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    Diante da escassa elaboração de pesquisas sobre a rotatividade da força de trabalho no setor público de saúde no Brasil, este estudo objetivou avaliar o índice dessa rotatividade na rede municipal de saúde de Belo Horizonte, Minas Gerais. A partir de reconhecida inscrição na literatura de um parâmetro para o índice de rotatividade na área hospitalar e com base na distribuição da frequência observada neste estudo, formalizou-se um novo parâmetro para a rede ambulatorial, bem como valores para os pontos de corte no que concerne à classificação dos seus níveis qualiquantitativos. Tais valores subsidiaram a análise do comportamento do índice de rotatividade em relação às seguintes variáveis: vínculos empregatícios, distritos sanitários, serviços de atenção à saúde, categorias profissionais e atenção primária e secundária à saúde. O índice geral de rotatividade na rede municipal no período estudado (julho de 2008 a junho de 2009) foi de 8,35%, que, mesmo diante da dificuldade de construção da base de dados, a qual adveio da existência de distintas fontes de informação, apresenta, em termos estatísticos, validade interna.<br>Given the scarcity of studies on workforce turnover rates in the public health care industry in Brazil, the purpose of this study was to assess this rate in the municipal health care network of Belo Horizonte, Minas Gerais. Based on the acknowledged inclusion of a turnover rate parameter for the hospital area in the literature and on the frequency distribution noticed in this study, a new parameter for the outpatient network and values for the cutoff points were made formal to classify turnover on the qualiquantitative levels. These values are the base for the analysis of the turnover rate concerning these variables: employment contracts, sanitary districts, health care services, professional categories and primary and secondary health care. The overall turnover rate in the municipal network in the studied period (July 2008 to June 2009) was 8.35% which, even considering the difficulties faced to build the database which derived from distinct sources of information has internal validity in statistical terms
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