Abstract Caffeine is naturally present in several foods, being one of the most consumed dietary ingredients in the world; however, excessive intake may cause health concerns. This study evaluated caffeine levels in teas and their infusions, the transference rate during brewing, and estimated caffeine intake from tea infusion. Brands and batches of 4 types of teas were analyzed for caffeine content by high performance liquid chromatography with a diode array detector. Mate tea was the one that presented lowest levels (6.1 to 13.2 mg/g) while Camellia sinensis teas were from 14.3 to 34.8 mg/g. There were statistical differences between different types, brands and batches. Caffeine levels in infusions followed the same pattern of the leaves, with mate tea presenting lowest levels. Caffeine percentage of transference from leaves to infusion varied from 51.5 to 85.2%. Caffeine intake was estimated to be up to 191.4 mg/day. Tea may be considered an important source of caffeine intake for heavy tea drinkers.

Os cloropropanóis, entre eles o 3-monocloropropano-1,2-diol (3-MCPD) e o 1,3-dicloropropan-2-ol (1,3-DCP), compreendem um grupo de contaminantes químicos com propriedades carcinogênicas e genotóxicas, encontrados em diversos alimentos processados e ingredientes alimentícios, como proteína vegetal hidrolisada, molho de soja, produtos à base de cereais, ingredientes derivados de malte e alimentos defumados. Este trabalho teve como objetivo avaliar a exposição ao 3-MCPD e 1,3-DCP pela dieta no Brasil e verificar se a presença destes compostos em alimentos pode representar um risco à saúde da população. A ingestão foi calculada combinando-se dados sobre o consumo alimentar, fornecidos pela Pesquisa de Orçamento Familiares 2008-2009, com os níveis de ocorrência dos contaminantes, determinados por cromatografia gasosa - espectrometria de massas. A exposição ao 3-MCPD variou de 0,06 a 0,51 µg.kg pc-1.dia-1 considerando médios e grandes consumidores, enquanto que a ingestão de 1,3-DCP foi estimada em 0,0036 µg.kg pc-1.dia-1 no pior cenário avaliado. Com base nesses resultados, verificou-se que a exposição aos cloropropanóis não representa um risco significativo à saúde da população brasileira. Entretanto, o consumo de determinados alimentos contendo altos níveis de 3-MCPD poderia ultrapassar a ingestão diária máxima tolerável provisória de 2 µg.kg pc-1 estabelecida para este composto e, assim, representar uma preocupação potencial.

Chloropropanols, including 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloropropan-2-ol (1,3-DCP), comprise a group of chemical contaminants with carcinogenic and genotoxic properties. They have been found in a variety of processed foods and food ingredients, such as hydrolyzed vegetable protein, soy sauce, cereal-based products, malt-derived ingredients, and smoked foods. This study aimed to assess the dietary exposure to 3-MCPD and 1,3-DCP in Brazil and verify whether the presence of these substances in foods could represent health risks. The intake was calculated by combining data on food consumption, provided by the Consumer Expenditure Survey 2008-2009, with the levels of contaminant occurrence determined by gas chromatography-mass spectrometry. The exposure to 3-MCPD ranged from 0.06 to 0.51 µg.kg bw-1.day-1 considering average and high consumers, while the intake of 1,3-DCP was estimated to be 0.0036 µg.kg bw-1.day-1 in the worst case scenario evaluated. Based on these results, it was verified that the Brazilians' exposure to chloropropanols does not present a significant health risk. However, the consumption of specific foods containing high levels of 3-MCPD could exceed the provisional maximum tolerable daily intake of 2 µg.kg bw-1 established for this compound and, therefore, represent a potential concern.

O teor de folatos nas principais espécies de cogumelos cultivados no Brasil foi avaliado neste trabalho. As espécies analisadas foram Agaricus bisporus (champignon de Paris), Lentinula edodes (shiitake) e Pleorotus ostreatus (shimeji). Foram determinadas as cinco principais formas de folatos presentes em alimentos: tetrahidro ácido fólico (THAF), 10-metil ácido fólico (10MAF), 5-metil tetrahidro ácido fólico (5MTHAF), 10-formil ácido fólico (10FAF) e 5formil tetrahidro ácido fólico (5FTHAF). A metodologia empregada utilizou extração com tampão fosfato, limpeza com ácido tricloroacético e separação das vitaminas por cromatografia líquida de alta eficiência, com detecção em série por fluorescência e ultravioleta. Os resultados obtidos para o total de folatos foram 551 a 1404 µg.100 g -1 para o champignon de Paris, 606 a 727 µg.100 g -1 para o shiitake e 460 a 1325 µg.100 g -1 para o shimeji. Os dados mostram que os cogumelos podem ser considerados fontes de folatos, e sua contribuição na dieta, para o aporte dessa vitamina, é significativa.

In this study, folates were evaluated in the main species of mushroom cultivated in Brazil. The species analysed were Agaricus bisporus (button mushroom), Lentinula edodes (shiitake) and Pleorotus ostreatus (shimeji). The five main forms of folate found in foods were determined: tetrahydrofolic acid (THFA), 10-methyl folic acid (10MFA), 5-methyl tetrahydrofolic acid (5MTHFA), 10-formyl folic acid (10FFA) and 5-formy tetrahydrofolic acid (5FTHFA). The methodology employed used extraction with phosphate buffer, clean up with trichloroacetic acid and separation of the vitamins by high-performance liquid chromatography, with simultaneous ultraviolet and fluorescence detection. The results obtained for total folate were 551 to 1404 µg.100 g -1 for the button mushroom, 606 to 727 µg.100 g -1 for shiitake and 460 to 1325 µg.100 g-1 for shimeji. The data showed that mushrooms could be considered as sources of folates and that their contribution of these vitamins to the diet was meaningful.

O objetivo desse trabalho foi avaliar e comparar a composição centesimal, teor de ácido ascórbico, fibra alimentar e fósforo dos cogumelos mais cultivados no Brasil (Agaricus bisporus, Lentinula edodes e Pleorotus spp.). Cinco amostras de diferentes lotes e marcas, de cada espécie de cogumelo, foram analisadas segundo os métodos descritos pela "Association of Official Analytical Chemists International". Para sólidos totais, proteína, lipídeo, cinzas, carboidratos e fibra alimentar os valores médios obtidos, em base seca, foram, respectivamente: 9,37; 23,22; 4,71; 8,89; 63,17; e 34,0 g.100 g -1. Para fósforo e ácido ascórbico os valores médios encontrados em base úmida foram de 104,13 e 6,67 mg.100 g -1, respectivamente. A avaliação da composição centesimal dos cogumelos estudados mostrou ser um alimento com características nutricionais excelentes, com alto teor de proteínas e fibras alimentares, além do baixo teor de lipídeos e fonte considerável de fósforo; apresentaram, entretanto, baixo teor de ácido ascórbico.

The aim of this study was to evaluate and to compare the proximate composition, vitamin C (ascorbic acid), dietary fiber and phosphorus contents of the more cultivated mushrooms in Brazil (Agaricus bisporus, Lentinula edodes, and Pleorotus spp.). Five different batches, from different brands of each mushroom were analyzed according to methods described in the Association of Official Analytical Chemists International. For total solids, protein, fat, ash, carbohydrates and dietary fiber, the average values, on a dry weight basis, were respectively: 9.37, 23.22, 4.71, 8.89, 63.17 and 34.0 g.100 g -1. For phosphorus and vitamin C, the average values on a wet weight basis were: 104.13 and 6.67 mg.100 g -1. From their compositions, the mushrooms studied here were shown to be excellent nutritional foods, presenting high protein and dietary fiber contents, low fat contents and reasonable sources of phosphorus, although poor vitamin C sources.