Matheus Francisco da Paz

Características tecnológicas de pães elaborados com farelo de arroz desengordurado

O objetivo deste trabalho foi avaliar a substituicao, em diferentes niveis (5, 10 e 15%), da farinha de trigo por farelo de arroz desengordurado, sobre as caracteristicas: capacidade de absorcao de agua, perda de massa ao fornear, volume especifico, perfil texturometrico e cor da casca e do miolo dos paes. Os resultados demonstram que o farelo de arroz desengordurado nao apresentou influencia em relacao a capacidade de absorcao de agua, em contrapartida, teve forte influencia na perda do peso ao fornear, mesmo para substituicoes de 5%. No entanto, tal substituicao nao afetou o volume especifico (p>0,05). Resultado semelhante foi observado para o perfil de textura, onde substituicoes de 10 e 15% demonstraram afetar, principalmente, a dureza dos paes analisados. Para a cor, a adicao do farelo de arroz desengordurado apresentou efeito negativo para a luminosidade do miolo e da casca, principalmente em substituicoes superiores a 5% para casca e 10% para o miolo. Entretanto, a substituicao da farinha de trigo por 5% de farelo de arroz desengordurado demonstrou uso potencial para aplicacao em produtos panificaveis.

Home composting using different ratios of bulking agent to food waste

The negative environmental impacts associated with home composting may be due to the absence of a defined operation criteria for the degradation process. In addition to the potentially low environmental impact in terms of energy and water usage, which is minimal to the manufacture of the composting unit and avoiding the processing and transportation of waste or byproduct, composting at home can also promote a reduction in the emission of unpleasant gases. The proportion of the food waste and bulking agents in the composting mixture may be decisive to fulfill good practices of waste stabilization. The aim of this study was to investigate how different ratios of bulking agent and organic household waste can affect the progress and outcome of the composting process. Three treatments, varying in the ratio of rice husk: raw fruit and vegetable leftovers (70:30, 50:50, 30:70; v:v) were used in a home composting system on a pilot scale. Results show that the proportion of starting materials used in the composting mixture influenced the degradation of organic matter, nitrogen dynamics of the process and its toxicity on germinating plants. The proportions with greater amounts of food waste had higher concentrations of mineral matter, higher peak temperature, and a better initial carbon-to-nitrogen ratio, while the proportion containing 70% of bulking agent lacked odors and leachate generation and showed a low nitrogen loss. A higher proportion of food waste presented better conditions for microbiological development and less time to obtain characteristics of matured composts. A higher proportion of bulking agents resulted in favorable conditions for household handling and less potential for environmental impacts.

A INFORMAÇÃO COMO INSTRUMENTO DE EFICIÊNCIA PARA O PROGRAMA DE COLETA SELETIVA NOS BAIRROS DE UMA CIDADE NO SUL DO BRASIL

Desde 2010, com a promulgacao da Politica Nacional de Residuos Solidos (PNRS) e exigido que os municipios possuam um Programa de Coleta Seletiva (PCS), com intuito de recolha de materiais passiveis de reciclagem . Nesse cenario, o objetivo do presente estudo foi identificar os aspectos informativos que determinam a eficiencia de um programa de coleta seletiva junto a populacao residente nos bairros da cidade de Pelotas-RS. A metodologia utilizada foi de questionario s aplicados a populacao residente nos bairros do municipio em questao , totalizando um total de 382 de populac ao amostrada. Foi averiguado que 90,67 % dos entrevistados afirmaram ter conhecimento sobre a diferenciacao dos residuos orgânico e reciclavel , 73,67 % segregam os residuos em suas residencias e 91,25% conhecem o PCS. O estudo permitiu concluir que independente do grau de escolaridade dos entrevistados, nem sempre a coleta seletiva e executada, visto que nao ha conhecimento do acompanhamento dos residuos apos o encaminhamento destes a coleta municipal.

Staphylococcus xylosus fermentation of pork fatty waste: raw material for biodiesel production

The need for cleaner sources of energy has stirred research into utilising alternate fuel sources with favourable emission and sustainability such as biodiesel. However, there are technical constraints that hinder the widespread use of some of the low cost raw materials such as pork fatty wastes. Currently available technology permits the use of lipolytic microorganisms to sustainably produce energy from fat sources; and several microorganisms and their metabolites are being investigated as potential energy sources. Thus, the aim of this study was to characterise the process of Staphylococcus xylosus mediated fermentation of pork fatty waste. We also wanted to explore the possibility of fermentation effecting a modification in the lipid carbon chain to reduce its melting point and thereby act directly on one of the main technical barriers to obtaining biodiesel from this abundant source of lipids. Pork fatty waste was obtained from slaughterhouses in southern Brazil during evisceration of the carcasses and the kidney casing of slaughtered animals was used as feedstock. Fermentation was performed in BHI broth with different concentrations of fatty waste and for different time periods which enabled evaluation of the effect of fermentation time on the melting point of swine fat. The lowest melting point was observed around 46 °C, indicating that these chemical and biological reactions can occur under milder conditions, and that such pre-treatment may further facilitate production of biodiesel from fatty animal waste.