Desenvolvimento de filmes biodegradáveis ativos a base de amido de milho adicionados de extrato de própolis

Abstract

The use of biodegradable polymers is an alternative to reduce the negative impacts from the disposal of synthetic plastic materials into the environment. Starch stands out as one of the raw materials in the production biodegradable materials, because of its high availability, renewability and low cost. Its limitations can be overcome by modifying methods such as acid modification, altering the physicochemical properties of starch resulting in films and coatings resistant. Because of the great importance to the protection and safety of food and beverages during distribution and storage, active packaging have been widely studied as antimicrobial films. When antimicrobial substance are incorporated or immobilized on the packaging material they are able to kill or inhibit spoilage and pathogenic microorganisms. Natural antimicrobial agents have drawn the attention of researchers as propolis, reported as effective against pathogenic bactéria. In this work films composed by acid-modified corn starch added with propolis extract in three different concentrations (1,2%, 1,5%, 1,8%). The antimicrobial activity of the films was evaluated against Staphylococcus aureus, Escherichia coli, Salmonella, Pseudomonas e Aeromonas, presenting effective in inhibiting Staphylococcus aureus for the three concentrations tested, there was an increase of the inhibition halo as a 3% increase in the concentration of the propolis extract. Propolis extract incorporation in films led to the improvement in tensile strength of the material relative to the formulation without the addition of this compound.