Determination of water content in Brazilian honeybee-collected pollen by Karl Fischer titration

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)This paper assesses the performance of a chemical method based on the Karl Fischer titration to determine the water content in samples of dehydrated honeybee-collected pollen. The following analysis parameters were investigated: extraction temperature, particle size, reaction time, and weight of a dried pollen sample. After optimization, the method was used to determine the water content of 154 samples of dried honeybee-collected pollen from different geographical regions of Brazil. The Karl Fischer titration method, performed using a solvent mixture of methanol and n-octanol (1:1 v/v) at 50 degrees C on pollen particles 600 mu m in size produced the best results. Mean values for water content of the 154 samples of dried honeybee-collected pollen from 12 Brazilian regions ranged from 3% to 9%. (C) 2011 Elsevier Ltd. All rights reserved.221016041608Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

PHYSICOCHEMICAL COMPOSITION OF BEE POLLEN FROM ELEVEN BRAZILIAN STATES

The physicochemical composition (ash, lipid, protein, glucose, fructose and free acidity) of Brazilian bee pollen (154 samples) from 23 production sites of 11 Brazilian states was analyzed. The data showed wide within-state and between-state variations: 133 to 4.13 g/100 g for ash, 4.01 to 13.32 g/100 g for lipid, 12.28 to 27.07 g/100 g for protein, 6.99 to 21.85 g/100 g for glucose, 12.59 to 23.62 g/100 g for fructose, and 105.3 to 609.9 meq/kg for free acidity. The:results are compared to data obtained in previous studies and the regulatory quality standards and the nutritive value for the human diet are discussed.55210711

Inorganic Contaminants in Bee Pollen from Southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)A set of experiments was carried out to validate a method for inorganic contaminants in honeybee-collected pollen, consisting of digestion of the samples in a closed microwave-assisted system and quantification of 10 inorganic contaminants by ICP OES. Forty-three samples of Brazilian bee pollen, collected in southeastern Brazil during one year, were analyzed. Determination of these analytes is important both as bioindicators of pollution and to verify the safety of consuming the pollen itself. The method had satisfactory performance, with good accuracy and precision. The ranges of the mean levels were 10.4-268.0 mg/kg for Al, Minas Gerais > Espirito Santo. Generally higher levels of all studied contaminants were observed in samples produced in an urban site, compared to those of a rural site. Al, Cd, Co, and Pb tended to have higher levels during the dry months (July-October). Ingestion estimates showed that Al and As would have the highest contributions to the adult diet, reaching 27 and 8%, respectively, of the provisional tolerable weekly intake (PTWI) values, considering a daily portion of 25 g.581168766883Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)UNASPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

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