Determinação de minerais em vísceras de frango cozidas em diferentes panelas e em amostras de sais e temperos por espectrometria atômica

Chicken meat and seasonings are important products for nutrition and economy. In this study, the levels of minerals were evaluated in edible chicken tissues, seasonings and kitchen salts. Samples of edible chicken tissues were analyzed raw and cooked with seasonings in different cooking pots commonly used in Brazil: iron, aluminum and hammered aluminum pot. Microwave-assisted acid digestion was used to sample decomposition. The levels of the metallic elements Al, Ca, Cu, Fe, Mn and Ni were determined by Microwave Induced Plasma Optical Emission Spectrometry. The limits of quantification were below 0.52 mg kg-1, showing to be adequate to the analytes levels; deviations were below 13 % showing good precision. The cooking in different pots promoted a decrease of Ca, Ni and moisture contents and an increase in the protein and ash concentration. Liver cooked in both iron and hammered aluminum pots presented similar Fe contents. The concentrations of Ca, Cr, Fe, K, Mg, Na and Zn in 15 samples of seasonings from different brands commercially available in Brazil were determined by Atomic Absorption Spectrometry, after microwave-assisted digestion. The method showed good accuracy with recovery ranges between 91 and 109% for addition to recovery tests and between 93 and 107% for the analysis of a certified reference material. The limits of quantification ranged from 0.061 (Cr) to 69 (K) mg kg-1 . The standard deviations were below 13%, indicating good precision. The ready-to-eat spices showed the highest Na levels among the samples studied. The levels of Ca, Fe, K, Mg and Na were determined in 23 samples of common and gourmet salts by spectrometric techniques after dissolution using diluted nitric acid. No matrix effects were observed when aqueous calibration was compared to the standard addition method. The accuracy of the method was assessed by addition and recovery tests, with ranges from 94 to 109%. The limits of quantification ranged from 3.3 (Fe) to 76 (K) mg kg-1. The standard deviations were below 3% showing a good precision also. Principal component analysis showed that some Himalayan salts had similar Ca and Mg contents among different samples. Blue Persian salts and low-sodium salts had the highest K concentration levels. In addition, the Hawaiian black salts presented similar Na and Fe concentrations. In relation to the concentration of the analytes in general, the results suggest that these types of salts cannot be considered to be a source of Ca, Fe, and Mg, contrary to the widespread statements found in popular media. With respect to the Himalayan samples' authenticity, both UV-VIS spectrophotometry and FT-Raman spectroscopy were used to investigate the presence of ordinary colorants E122 and E124 in commercial samples, and no evidence of adulteration or fraud was observed.Temperos e vísceras de frango são importantes do ponto de vista econômico e nutricional. Neste estudo, determinaram-se os teores de em tecidos comestíveis de frango, especiarias, temperos industrializados e sais de uso culinário. Amostras de tecidos de frango foram analisadas cruas e cozidas em diferentes panelas utilizadas no Brasil: panela de ferro, de alumínio e de alumínio fundido. A digestão assistida por radiação micro-ondas foi empregada para decomposição das amostras. Os teores dos elementos metálicos Al, Ca, Cu, Fe, Mn e Ni foram determinados por espectrometria de emissão óptica com plasma induzido por micro-ondas. Os limites de quantificação ficaram abaixo de 0,52 mg kg-1, mostrando detectabilidade adequada para o nível dos analitos; os desvios padrões relativos ficaram abaixo de 23 %, indicando boa exatidão. A cocção das amostras de frango promove redução dos teores de Ca, Ni e umidade e aumento dos teores de proteínas e cinzas, independente do tipo de panela utilizada. Os teores de ferro obtidos para a amostra de fígado cozida nas panelas de ferro e de alumínio fundido são comparáveis, evidenciando que a cocção em panela de ferro não é significativa para melhorar o aporte desse nutriente na alimentação. Quanto ao estudo das ervas e temperos, a digestão ácida assistida por radiação micro-ondas foi utilizada para determinação dos teores de Ca, Cr, Fe, K, Mg, Na e Zn em 15 amostras de especiarias e temperos prontos por espectrometria atômica. A exatidão das análises foi avaliada por ensaios de adição e recuperação, com valores entre 91 e 109 %, e pela análise de material de referência certificado, com recuperações entre 93 e 107 %, indicando boa exatidão. Os limites de quantificação variaram de 0,061 (Cr) a 69 mg kg-1 (K); os desvios ficaram abaixo de 13 %, indicando uma boa precisão. As amostras de temperos prontos apresentam teores de Na maiores que as amostras de alho, louro e pimenta. Observou-se uma grande variação dos teores de Fe e Zn em amostras de especiarias e de Ca e K em amostras de temperos prontos, não havendo um perfil para a concentração desses elementos. Os teores de Ca, Fe, K, Mg e Na foram determinados em 23 amostras de sal culinário por técnicas espectrométricas após dissolução empregando ácido nítrico diluído. A exatidão do método foi avaliada por ensaios de adição e recuperação, com resultados entre 94 a 109 %; os limites de quantificação variaram de 3,3 (Fe) a 76 mg kg-1 (K). Os desvios padrões relativos ficaram abaixo de 3 %, mostrando a boa precisão. As amostras de sal azul da Pérsia e sal light apresentam os maiores teores de K, enquanto as amostras de sal negro do Havaí apresentam teores de Na e Fe similares. Contudo, os níveis encontrados dos analitos indicam que esses sais não são fontes significativas de minerais. A presença dos corantes E122 e E124 nas amostras de sal rosa do Himalaia foi investigada usando o método espectrofotométrico e a espectroscopia Raman como um método alternativo. Não foram encontradas evidências de adulterações no conjunto de amostras analisado.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Classification Of Frankfurters By Ft-raman Spectroscopy And Chemometric Methods.

Frankfurters are widely consumed all over the world, and the production requires a wide range of meat and non-meat ingredients. Due to these characteristics, frankfurters are products that can be easily adulterated with lower value meats, and the presence of undeclared species. Adulterations are often still difficult to detect, due the fact that the adulterant components are usually very similar to the authentic product. In this work, FT-Raman spectroscopy was employed as a rapid technique for assessing the quality of frankfurters. Based on information provided by the Raman spectra, a multivariate classification model was developed to identify the frankfurter type. The aim was to study three types of frankfurters (chicken, turkey and mixed meat) according to their Raman spectra, based on the fatty vibrational bands. Classification model was built using partial least square discriminant analysis (PLS-DA) and the performance model was evaluated in terms of sensitivity, specificity, accuracy, efficiency and Matthews's correlation coefficient. The PLS-DA models give sensitivity and specificity values on the test set in the ranges of 88%-100%, showing good performance of the classification models. The work shows the Raman spectroscopy with chemometric tools can be used as an analytical tool in quality control of frankfurters.1918980-9

Multivariate approach to assess in vitro Fe bioaccessibility in chicken meat

A 32 factorial design was employed to develop an in vitro digestion method for estimation of Fe bioaccessible fractions in cooked chicken meat. The effects of sample size and the in vitro bioaccessible fractions of this essential element were evaluated. A sample preparation method employing a microwave assisted digestion with dilute nitric acid was used prior to total Fe determination. For the bioacessibility studies, the optimized procedure employed 7.5 g of sample and 6% w/v of an acid pepsin solution. This procedure was applied to two kinds of chicken meat samples: breast and liver. Flame Atomic Absorption Spectrometry was used to determine total and bioaccessible (chyme or soluble portion) levels of iron in the samples. With respect to total Fe content, the bioaccessible fractions of Fe found in these samples were around 23% and 56 %, for breast and chicken liver, respectively. The chicken liver sample showed the highest total (400 ± 10 mg kg-1) and bioaccessible Fe contents (223 ± 18 mg kg-1) and stands out as a good source of this micronutrient.

Determination of composition, calcium partition and calcium bioaccessibility in marketed Minas Padrão cheeses

Cheeses have a prominent position among dairy products due to their high lipid, protein and mineral content. This work aimed to evaluate twelve Minas Padrão cheeses marketed in Juiz de Fora. The analyzes were carried out when the cheeses were between 15 days and 30 days of manufacture in order to evaluate the composition constituents of relevance for classification in the Technical Regulation of Cheese Identity and Quality, to evaluate the hydrogen ionic potential (pH), calcium distribution (fractions of total calcium, calcium in the aqueous phase and free calcium) and bioaccessibility of calcium. The mean values found were: 42.4 ± 3.8 % w/w moisture; 22.5 ± 1.4 % w/w protein; 26.7 ± 1.9 % w/w of fat; 46.3 ± 2.7 % fat in the dry matter; 687 ± 86 mg/100g of total calcium; 482 ± 139 mg/100g of calcium in the aqueous phase; 99.3 ± 10.7 mg/100 mL of free calcium; 37.1 ± 13.5% of bioaccessibility of calcium; 5.14 ± 0.20 pH value. The lack of a Brazilian regulation for Minas Padrão cheese makes it difficult to characterize the product. In relation to the calcium, most of this mineral present in the cheese is in its aqueous phase, associated with the salts. The bioaccessible content of calcium in commercial Minas Padrão cheeses varies widely, by different causes. This paper contributes to value nutritionally this kind of cheese and present data in order to improve the Technical Regulation of Cheese Identity and Quality he Minas Padrão cheese, through the unprecedented characterization of this food in terms of content, partition between phases (aqueous and free) and bioaccessibility of calcium

A importância da esporotricose felina no contexto da saúde única: Revisão: The importance of feline sporotrhichosis in the contexto of single health: Review

A esporotricose é uma micose subcutânea causada por agentes fúngicos do gênero Sporothrix. Acomete diferentes espécies de animais domésticos e silvestres, sendo o gato doméstico o principal reservatório urbano, e por acometer humanos, configura-se como uma zoonose. A transmissão ocorre pelas formas zoonótica e geofílica. Além disso, é importante ressaltar que a esporotricose é uma zoonose de grande importância para a saúde única tendo em vista os danos físicos causados nos animais e humanos, e os transtornos mentais nas pessoas, em virtude da aparência e odor da lesão. Dado o exposto, o objetivo do presente trabalho é proporcionar uma maior visibilidade a esta doença que ainda é negligenciada mesmo diante dos sérios impactos que causa na saúde única. Foi realizada uma revisão de literatura com base em livros da medicina veterinária, periódicos e artigos científicos extraídos do Google acadêmico, Scielo e Pubmed. Ao fim do trabalho, conclui-se a importância de realizar artigos científicos acerca da temática, em virtude da sua relevância para o âmbito social, econômico e ocupacional

Solubilização de amostras biológicas visando a determinação de chumbo e ferro por espectrometria de absorção atômica

This study describes the determination of total content of lead and iron in chicken meat samples commercialized in the city of Juiz de Fora, Brazil. In addition to the total content, determined in heart cuts, thigh, liver, gizzard, breast and drumstick, iron bioaccessible fraction in breast and liver cuts was determined after cooking in iron pot. The analytes levels were determined by atomic absorption spectrometry. The total lead content was determined by graphite furnace atomization after two sample preparation methods: microwave-assisted acid digestion, using dilute acid solutions and solubilization in an alkaline medium, using TMAH® reagent. In both preparation methods, it was not possible to quantify the analyte because the levels found were below the limit of quantification. However, the signals of integrated absorbance, limits of detection (Acid medium: 0.097 μg kg-1 and Alkaline medium: 0.099 μg kg-1) and quantification (Acid medium: 0.32 μg kg-1and Alkaline medium: 0.33 μg kg-1) and characteristic mass (Acid medium: 10 pg and Alkaline medium: 13 pg) obtained for the lead after two sample preparations showed the same order of magnitude, demonstrating that the sample preparation in alkaline medium is a good alternative to acid digestion due to its higher analytical frequency and also it suits the routine analysis. Both methods for lead were evaluated in terms of accuracy, with deviations smaller than 15%, and through addition to recovery tests, with ranges between 83 and 110%. The total and bioaccessible iron fractions were determined by flame atomization after acid mineralization and in vitro gastrointestinal digestion simulation method, respectively. The raw viscera cuts had total iron content larger than those of muscle samples with differences up to 87%. The accuracy and precision of the method were evaluated through recovery tests and analysis of certified reference material, with range between 91-110% of recovery and deviations less than 5%. The iron bioaccessible fractions in breast and liver after cooking in iron pot were 23% and 56%, respectively, which indicates that liver is a good source of iron. The Raman spectroscopy was used to monitor the mechanisms of solubilization of raw chicken cuts in alkaline medium. The results indicate that TMAH® acts in the decomposition of some compounds such as amino acids, carbohydrates, lipids and proteins, due to changes in the spectral profile of the samples before and after the treatment. These data indicate that this type of preparation can be used for the extraction of metals bound exclusively to these compounds.Este trabalho descreve a determinação dos teores totais de chumbo e ferro em amostras de carne de frango comercializadas na cidade de Juiz de Fora, Brasil. Além do teor total, determinado nos cortes coração, coxa, fígado, moela, peito e sobrecoxa, os teores bioacessíveis de ferro nos cortes de fígado e peito após cocção em panela de ferro também foram determinados. Os teores dos analitos foram determinados por espectrometria de absorção atômica. Os teores de chumbo total foram determinados por atomização em forno de grafite após dois métodos de preparo de amostra: mineralização ácida assistida por microondas empregando soluções diluídas de ácido e solubilização em meio alcalino utilizando o reagente TMAH®. Em ambos os métodos de preparo não foi possível quantificar o analito, pois os teores encontrados estavam abaixo do limite de quantificação. Todavia, os sinais de absorbância integrada, os limites de detecção (Meio ácido: 0,097 μg kg-1 e Meio alcalino: 0,099 μg kg-1) e quantificação (Meio ácido: 0,32 e Meio alcalino: 0,33 μg kg-1) e a massa característica (Meio ácido: 10 e Meio alcalino: 13 pg) obtidos para o chumbo após os dois preparos apresentaram a mesma ordem de grandeza. Assim, o preparo em meio alcalino apresenta-se como uma boa alternativa às digestões ácidas por apresentar maior frequência analítica e se adequar a análises de rotina. Ambos os métodos para o chumbo foram avaliados em termos de precisão, com desvios menores que 15 %, em termos de exatidão por meio de ensaios de adição e recuperação, apresentando faixas entre 83 e 110 % de recuperação. Os teores de ferro total e bioacessível foram determinados por atomização em chama após mineralização ácida e simulação in vitro da digestão gastrointestinal, respectivamente. Os cortes de vísceras cruas apresentaram um teor total de ferro maior que os das amostras de músculo, com uma diferença de até 87 %. A exatidão e precisão do método foram avaliadas por ensaios de adição e recuperação e análise de material de referência certificado, com valores entre 91 e 110 % de recuperação e desvios menores que 5 %. As frações bioacessíveis em peito e fígado, após cocção em panela de ferro, foram de 23 e 56 %, respectivamente, indicando que o fígado é uma boa fonte de ferro. A Espectroscopia Raman foi utilizada para o monitoramento dos mecanismos de solubilização dos cortes de frango crus em meio alcalino. Os resultados indicam que o TMAH® atua na decomposição de compostos como aminoácidos, carboidratos, lipídios e proteínas, devido a mudanças do perfil espectral das amostras antes e após o tratamento. Estes dados indicam que este tipo de preparo pode ser empregado para extração de metais ligados exclusivamente a estes compostos.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Multivariate approach to assess in vitro Fe bioaccessibility in chicken meat

Abstract A 32 factorial design was employed to develop an in vitro digestion method for estimation of Fe bioaccessible fractions in cooked chicken meat. The effects of sample size and the in vitro bioaccessible fractions of this essential element were evaluated. A sample preparation method employing a microwave assisted digestion with dilute nitric acid was used prior to total Fe determination. For the bioacessibility studies, the optimized procedure employed 7.5 g of sample and 6% w/v of an acid pepsin solution. This procedure was applied to two kinds of chicken meat samples: breast and liver. Flame Atomic Absorption Spectrometry was used to determine total and bioaccessible (chyme or soluble portion) levels of iron in the samples. With respect to total Fe content, the bioaccessible fractions of Fe found in these samples were around 23% and 56 %, for breast and chicken liver, respectively. The chicken liver sample showed the highest total (400 ± 10 mg kg-1) and bioaccessible Fe contents (223 ± 18 mg kg-1) and stands out as a good source of this micronutrient

The relative contribution of environmental and spatial factors on the composition of assemblages of Chironomidae (Insecta, Diptera) in Atlantic Forest springs

Environmental and spatial factors can affect the distribution of aquatic insect metacommunities. In tropical springs, few studies have been conducted on the subject, especially regarding the influence of spatial variables. Our main objective was to assess the influence of environmental and spatial factors on the composition of Chironomidae assemblages in 48 pristine springs in different watersheds in Minas Gerais state, Brazil. This is the first study of the composition of Chironomids assemblages in springs in the Neotropical region. A single time in the dry season, three samples of the substrate at each spring were collected with a hand net. To assess the importance of environmental and/or spatial predictors of the composition of the Chironomidae metacommunities Partial redundancy analysis was performed. The results show that environmental variables explained little of the composition of Chironomids assemblages in Atlantic Forest springs. The local environmental factors selected by the model were dissolved oxygen, conductivity and plant cover, and the spatial factors selected were PCNM 1 and PCNM 6. Most of the variation in the Chironomidae assemblage remained unexplained by the partial redundancy models. Our results suggest the influence of temporal and spatial variables on the structure of metacommunities of Chironomidae in tropical springs.</p