Development of alginate beads with encapsulated jabuticaba peel and propolis extracts to achieve a new natural colorant antioxidant additive.

This work aims to encapsulate anthocyanins and phenolic compounds extracted from a native Brazilian fruit peel - jabuticaba (Plinia cauliflora (Mart.) Kausel) and propolis from Tubuna (Scaptotrigona bipunctata) stingless bees, with great potential benefits for human health. The alginate encapsulation was conducted by the ionotropic gelation through the dripping into the CaCl2 solution. Both raw extracts were characterized by TPC - total phenolic content (Folin-Ciocalteu), AA -antioxidant activity (DPPH and ABTS assays), and TMAC - total monomeric anthocyanin concentration (pH differential method); as well as their resultant mixture (2:1 jabuticaba/propolis). The obtained beads presented highly efficient encapsulation of total polyphenols (~98%) and monomeric anthocyanins (~89%), with spherical morphology and smooth surface obtaining a mean diameter between 200 and 250 µm. In vitro release study showed that JPE/alginate beads were completely disintegrated at pH 7.4 (intestinal pH), but they were resistant to gastric pH (1.2) presenting a slow release of about 40% in 240 min. This is the first report that encapsulates the mixture of jabuticaba and propolis extracts and may contribute to the utilization of a great source of bioactive compounds besides the potential pigment of anthocyanins, an alternative to natural and healthy food/beverage colorants.

Medicina das viagens: generalidades sobre medicina das viagens

Este programa apresenta algumas generalidades sobre medicina das viagens nomeadamente, alguns cuidados que o viajante deve ter antes, durante e após uma viagem para regiões tropicais. Participação de Mário de Matos, presidente da Agência de Viagens Top Tours, de Fátima Leão, de Magda Monteiro e do fotógrafo Rui Carvalho, viajantes. Referência videográfica: Atouguia, Jorge - Medicina das viagens [Em linha] : generalidades sobre medicina das viagens. Realização de Paulo Cartaxo; Tecnólogo Vítor Almeida. Lisboa : Universidade Aberta, 2000. 1 prog. vídeo (27 min., 38 seg.) Link do vídeo: https://vimeo.com/user34119652/review/147106448/bf604fde92

Modeling of drying and adsorption isotherms of the fish feed

The aim of this work was to study the drying curves and equilibrium isotherms of extruded fish feed. The drying curves were determined at air temperatures of 50, 60, 70 and 80°C and airflow velocities of 1.5, 2.5 and 3.5 m/s). The equilibrium isotherms of relative humidity of air were obtained between 10 and 80 percent at 30, 40, 50, and 70°C. The experimental data were fitted for non-linear regression by using Statistica® to the models reported in the literature. The results showed that the drying curves and the equilibrium isotherms were significantly influenced by variations of the air temperature in a similar way to solid materials as described in the literature. The statistical results for models of Page and Peleg showed that the fitting of the experimental drying curve and isotherm data were satisfactory.

Modeling, simulation, and analysis of a reactor system for the generation of white liquor of a pulp and paper industry

An industrial system for the production of white liquor of a pulp and paper industry, Klabin Paraná Papéis, formed by ten reactors was modeled, simulated, and analyzed. The developed model considered possible water losses by the evaporation and reaction, in addition to variations in the volumetric flow of lime mud across the reactors due to the composition variations. The model predictions agreed well with the process measurements at the plant and the results showed that the slaking reaction was nearly complete at the third causticizing reactor, while causticizing ends by the seventh reactor. Water loss due to slaking reaction and evaporation occurred more pronouncedly in the slaker reactor than in the final causticizing reactors; nevertheless, the lime mud flow remained nearly constant across the reactors.

Effect of water losses by evaporation and chemical reaction in an industrial slaker reactor

A dynamic model of the slaker reactor was developed and validated for Klabin Paraná Papéis causticizing system, responsable for white liquor generation used by the plant. The model considered water losses by evaporation and chemical reaction. The model showed a good agreement with the industrial plant measures of active alkali, total titratable alkali and temperature, without the need of adjustment of any parameter. The simulated results showed that the water consumption by the slaking reaction and evaporation exerted significant influence on the volumetric flow rate of limed liquor, which imposed a decrease of 4.6 percent in the amount of water in reactor outlet.

Foi desenvolvido e testado um modelo dinâmico do reator de apagamento do sistema de caustificação da Klabin Paraná Papéis, responsável pela geração do licor branco utilizado na planta. O modelo contempla perdas de água por evaporação e por reação química e apresentou boa concordância com dados industriais de álcali ativo, álcali total titulável e temperatura, sem a necessidade de ajuste de nenhum parâmetro. Os resultados obtidos a partir de simulações revelam que o consumo de água pela reação de apagamento, bem como pela evaporação, exercem uma influência significativa sobre a vazão volumétrica na saída do reator, impondo uma diminuição de 4,6 por cento sobre o teor de água na corrente de saída do reator em relação à alimentação.