SciELO - Scientific Electronic Library Online

vol.42 issue2Phytochemical study of Mikania pseudohoffmanianna G. M. Barroso ex W. C. HolmesDetermination of urinary phenol by gas chromatography in workers using phenolic resins in foundries author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Revista Brasileira de Ciências Farmacêuticas

Print version ISSN 1516-9332


ARAUJO, Adriano Antunes de Souza et al. Determination of humidity and ash content of guarana commercial samples using conventional method and thermal analysis. Rev. Bras. Cienc. Farm. [online]. 2006, vol.42, n.2, pp.269-277. ISSN 1516-9332.

Paullinia cupana Kunth a vegetable popularly known as guarana, belongs to the Sapindaceas plant family and is predominant in the Amazon region. The low quality of this product can be attributed to the species and less noble varieties, harvest techniques and/or inadequate processing or, yet due to addition of substances that are not included in its natural composition. The main goal of this work was to evaluate from thermogravimetry (TG)/derivative thermogravimetry (DTG) and differential scanning calorimetry (DSC), the thermal behavior of powdered guarana samples in the Brazilian market in order to evaluate the thermal behavior of guaraná powder samples commercialized in Brazil and to establish a comparative study between conventional and TG methods for humidity contents determination and ashes. In general, the samples did not present significant differences in the DSC curves profiles and TG/DTG. The thermogravimetry showed that it is possible to decrease the time of the analysis using less amount of sample and allowed to determine humidity and ashes contents. In relation to conventional method the errors of analysis inherent of the samples manipulation were decreased. The thermoanalytical techniques have shown potential applications in the determination of technological parameters, such as: quality control, toasting and adequate stock conditions.

Keywords : Paullinia cupana; Guarana; Thermal analysis; Analytical chemistry.

        · abstract in Portuguese     · text in Portuguese     · Portuguese ( pdf epdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License