Efeito da adição de gelatina nas propriedades termodinâmicas e nas características de géis e películas biodegradáveis obtidos a partir de amido de mandioca

Abstract

The starch has been widely used in the food industry due to its power binder, thickener, binder or stabilizer, implying knowledge of the behavior of the gels produced as well as the changes of structure produced by the interaction of starch with the various ingredients of the formulations, as proteins, which have functions as a thickener solutions, gelling agent, emulsifying or foaming, in addition to the nutritional aspect in foods. The addition of protein to starch promotes significant changes in their properties extending the range of applications. In this study we evaluated the thermodynamic behavior of systems containing cassava starch as polysaccharide and gelatin as a protein source, analyzing degree of gelatinization, gelation kinetics spectrophotometer, phase separation (syneresis), differential scanning calorimetry (DSC) and a possible application using biodegradable films "casting" method. These results support the use of gelatin influenced the behavior of the gels, strengthening the network of them, making them more balanced and less susceptible to phase separation, making possible the use of these systems, especially in frozen products of high quality that require soft texture and a longer shelf life. Films based on cassava starch / gelatin proved to be visually homogeneous and easy detachment of the drying support, indicating a homogenous mixture of compounds. Increasing the concentration of gelatin in the mixture caused an increase in the mechanical resistance of bioplastics studied, as well as a decrease in the opacity of these important features and constantly sought by the food industry.