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1.
Heliyon ; 10(10): e31506, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38818199

RESUMO

Neo-formed contaminants (NFCs) are common in many foods, especially those subjected to high-temperature processing. Among these contaminants, products arising from the Maillard reaction, sugar reduction, thermal degradation of polyphenols and lipid oxidation, including acrylamide, furan, furfuryl alcohol, and hydroxymethylfurfural, are consistently linked to potential neoplastic effects. NFCs are found in globally traded commodities like coffee and cocoa, posing a significant risk due to their frequent consumption by consumers. A direct correlation exists between consumption frequency, exposure levels, and health risks. Hence, it's crucial to establish reliable methods to determine levels in both matrices, aiming to mitigate their formation and minimise risks to consumers. This review offers a comprehensive examination, discussion, and identification of emerging trends and opportunities to enhance existing methodologies for extracting and quantifying NFCs in coffee and cocoa. By presenting an in-depth analysis of performance parameters, we aim to guide the selection of optimal extraction techniques for quantifying individual NFCs. Based on the reviewed data, headspace extraction is recommended for furan, while solid and dispersive solid phase extractions are preferred for acrylamide when quantified using gas and liquid chromatography, respectively. However, it is worth noting that the reported linearity tests for certain methods did not confirm the absence of matrix effects unless developed through standard addition, leading to uncertainties in the reported values. There is a need for further research to verify method parameters, especially for determining NFCs like furfuryl alcohol. Additionally, optimising extraction and separation methods is essential to ensure complete compound depletion from samples. Ideally, developed methods should offer comprehensive NFC determination, reduce analysis time and solvent use, and adhere to validation parameters. This review discusses current methods for extracting and quantifying NFCs in coffee and cocoa, highlighting emerging trends and emphasising the need to improve existing techniques, especially for compounds like furfuryl alcohol.

2.
Talanta ; 218: 121133, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797890

RESUMO

This work propose the fabrication and characterization of a Pt microelectrode integrated with a silver quasi-reference counter electrode (Pt/AgQRCE) for real time amperometric measurements of hydrogen peroxide electrochemically generated by water oxidation on Nb-supported boron doped diamond (Ni/BDD) anode. The developed electroanalytical method requires a very small sample volume and has higher sensitivity when compared to the conventional spectrophotometric analysis using ammonium metavanadate. The experiments were performed with Nb/BDD anode applying current densities of 30, 60, 90 and 120 mA cm-2 in 0.10 mol L-1 HClO4 supporting electrolyte showed that H2O2 production increase in the first 90 min of electrolysis and then reaches a plateau in both off-line and real time measurements. For the first 90 min, the electrogeneration of H2O2 exhibited a pseudo zero-order kinetics. The results obtained by the electrochemical amperometric analysis were compared to a spectrophotometric methodology reported on the literature and, at 95% confidence level the two methods do not demonstrated significant difference.

3.
Sci Total Environ ; 676: 756-766, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31055207

RESUMO

An overview about the presence of arsenic (As) in groundwaters of Argentina, made by a transdisciplinary group of experts is presented. Aspects on As occurrence, effects of As on human health, regulations regarding the maximum allowable amount of As in drinking water as well as bottled water, and analytical techniques for As determination are presented. The most affected region in Argentina is the Chaco-Pampean plain, covering around 10 million km2, where approximately 88% of 86 groundwater samples collected in 2007 exceeded the World Health Organization (WHO) guideline value. In the Salí river basin, As concentrations ranged from 11.4 to 1660 µg/L, with 100% of the samples above the WHO guideline value. In the Argentine Altiplano (Puna) and Subandean valleys, 61% of 62 samples collected from surface and groundwaters exceeded the WHO limit. Thus, it can be estimated that, at present, the population at risk in Argentina reaches around four million people. Pathologies derived from the chronic consumption of As, the metabolism of As in the human body and the effects of the different As chemical forms, gathered under the name HACRE (hidroarsenicismo crónico regional endémico in Spanish, for chronic regional endemic hydroarsenicism) are described. Regarding the regulations, the 10 µg/L limit recommended by the WHO and the United States Environmental Protection Agency has been incorporated in the Argentine Food Code, but the application is still on hold. In addition, there is disparity regarding the maximal admitted values in several provinces. Considerations about the As concentrations in bottled water are also presented. A survey indicates that there are several Argentine laboratories with the suitable equipment for As determination at 10 µg/L, although 66% of them are concentrated in Buenos Aires City, and in the Santa Fe, Córdoba and Buenos Aires provinces. Conclusions and recommendations of this first part are provided.


Assuntos
Arsênio/análise , Exposição Ambiental/estatística & dados numéricos , Política Ambiental/legislação & jurisprudência , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Argentina , Exposição Ambiental/análise , Poluição Química da Água/legislação & jurisprudência , Abastecimento de Água/legislação & jurisprudência , Abastecimento de Água/estatística & dados numéricos
4.
Rev. cuba. farm ; 50(1)ene.-mar. 2016.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-844874

RESUMO

El sobrepeso y la obesidad son considerados un problema de salud pública a nivel mundial y a la postre, esa condición incentiva que millones de personas consuman productos para perder o controlar el peso. Dentro de este significativo mercado se puede encontrar una gran cantidad y variedad de productos que se comercializan con la denominación de origen natural. En la última década, se presenta que muchos de ellos son adulterados con sustancias sintéticas para potencializar su efecto. Una de las drogas sintéticas que se utiliza con ese propósito es la sibutramina, aun cuando fue retirada del mercado a nivel mundial en el año 2010 debido a sus graves efectos secundarios. En este trabajo se describen algunos ejemplos de casos importantes de adulteración de productos naturales en el orbe y las metodologías analíticas que se pueden utilizar en la determinación de su adulteración con sibutramina; luego de revisar y seleccionar artículos científicos de los últimos años y acceder a través de bases de datos Proquest, Scient Direct, Springer, EBSCO y otras del Sistema de Bibliotecas e Información de la Universidad de Costa Rica. Se encontró una variedad de técnicas y metodologías analíticas que permiten identificar y cuantificar la presencia de sibutramina en productos utilizados para bajar de peso(AU)


Overweight and obesity are considered as a public health problem worldwide and ultimately, this condition encourages millions of people to buy products for losing or controlling weight. In this significant market, it is possible to find a large number and great variety of products sold under the natural origin denomination. In the last decade, it has been found that many of them have been adulterated with synthetic substances to potentiate their effect. A synthetic drug that is used for this purpose is sibutramine, even though it was withdrawn from the worldwide market in 2010 because of its serious side effects. This paper described some significant examples of adulteration of natural products in the world and the analytical methodologies that can be used in determining the adulteration of these goods with sibutramine after reviewing and selecting scientific papers in recent years and access through databases Proquest, Scient Direct, Springer, EBSCO and others of the System of Libraries and Information at the University of Costa Rica. A range of techniques and analytical methods to identify and quantify sibutramine in slimming products was found(AU)


Assuntos
Humanos , Produtos Biológicos/uso terapêutico , Sobrepeso/epidemiologia , Obesidade/tratamento farmacológico , Cromatografia em Camada Fina/métodos , Costa Rica , Medicamentos de Referência
5.
São Paulo; s.n; 2009. 155 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-561047

RESUMO

No Brasil os dados sobre a utilização dos sulfitos pela indústria de alimentos e pesquisas sobre o seu consumo são escassos. Sendo assim, o objetivo desta pesquisa foi avaliar o nível de sulfitos em sucos de frutas e estimar seu consumo por escolares de 5ª. a 8ª. séries de escolas públicas, do ensino fundamental, do município de São Caetano do Sul-SP, Brasil. Foi aplicado questionário de freqüência de consumo de alimentos (QFCA) em 313 escolares, sendo 56,9 % do sexo feminino e 43,1 % do sexo masculino, com média de idade de 14,7 anos. Os alimentos sulfitados mais consumidos foram os néctares ou sucos de frutas, o açúcar refinado, as batatas fritas congeladas, o coco ralado, o suco de caju e as frutas secas e cristalizadas. Considerando os limites máximos permitidos (LMP) pela legislação brasileira, o consumo de SO2, em mg SO2/kg pc/dia, foi de 0,12 mg SO2/kg pc/dia, sendo que este valor médio corresponde a 17% da IDA (0,7 mg SO2/kg pc/dia). Já os resultados das análises dos sucos de frutas demonstram que a análise por injeção em fluxo (Flow injection analysis - FIA) modificada obteve resultados de sulfitos nas amostras analisadas com menor variação do que aqueles obtidos pelo método Monier-Williams (M-W) otimizado, e que nenhuma amostra ultrapassou os LMP.


In Brazil there are no data on use of sulphites by the food industry and research on their consumption by population. Thus, the objective of this research was to evaluate sulphites in fruits juices and estimate intake sulphites in a group of 5th 8th schoolchildren of public schools in São Caetano do Sul-SP, Brazil. It was applied a food frequency questionnaire (FFQ) at 313 schoolchildrens (56.9% female, 43.1% male and average age 14.7 years). Sulphited products identified were fruits juices, sugar, frozen chips, grated coconut, cashew juice and dried fruits. Considering maximum permitted levels (MPL) stabilished by Brazilian legislation, none of the students exceeded the ADI of 0.70 mg SO2/kg bw/day, with average of consumption of 0.12 mg SO2/kg bw/day (17 % of the ADI). The results of the fruits juices analysis demonstrated flow injection analysis (FIA) modified obtained better results than optimized Monier-Williams method (M-W) and no sample exceeded the MPL.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Estudantes/estatística & dados numéricos , Ingestão de Líquidos , Sucos , Sulfitos/análise , Fenômenos Fisiológicos da Nutrição do Adolescente , Aditivos Alimentares/toxicidade , Tecnologia de Alimentos , Comportamento Alimentar
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