Produção de embalagem biodegradável a base de amido de mandioca e gelatina para aplicação em produtos alimentícios

Abstract

The packaging use has been target of countless researches in the last decades. Each day newer technologies are being developed in order to perfect the biodegradable materials production. The production of these kinds of packaging stands out as an alternative to reduce the impacts caused by use of non-degradable polymers. One of the most studied biopolymers is the cassava starch due to its low cost and abundance. Many researches are being conducted to reduce the hydrophilicity from mixtures of starch and different polymers such as alginate, polyvinyl alcohol and gelatin. The gelatin is a polymer, Hydrocolloid of high solubility in water, but it produces films with good mechanical resistance. For the biodegradable films production, besides starch and proteins, polyols can be used in its formulation, such as glycerol, that act as a plasticizer of the starch molecules, changing the films flexibility. Annexation of antioxidants substances in films represents a promising path in the synthesis of active packaging. The açai (Euterpe oleraceae Martius) has attracted a lot of attention because of his nutritional value, with high content of anthocyanin in addition to is antioxidant and anti-inflammatory activity, what makes it a potential candidate for use in active packaging. The purpose of this paper was to develop an active biodegradable packaging using cassava starch and bovine gelatin with the annexation of açai (Euterpe oleraceae Martius) extract; characterize the packaging made and use it as an indicator for food quality. The casting technique was used to produce the packaging by setting the quantities of starch, gelatin and glycerol and varying the concentration of açai extract. The characterization was made by visual and tactile analysis, to thickness, permeation of water vapor (PVA), to traction resistance (RT), to elongation percentage (ELO), to thermic stability (DSC), to opacity, to humidity (UM), to water solubility, to color, to microstructure (MEV) and Fourier transform mid infrared spectroscopy (FTIF) and identify changes in the packaging color when submitted to different values of pH. Lastly, determine the antioxidant activity of the açai extract and the active packaging. It was possible to develop biodegradable packaging from cassava starch, gelatin, glycerol and açai extract (EAÇ) (0,25, 0,50, 0,75 g). The açai extract incorporation increased the thickness, PVA, SOL, UM and opacity in all formulations. RT and ELO values decreased, showing that the films became less rigid. The active packaging suffered color alterations in acid pH, going from a purple tone to a reddish tone. The antioxidant analysis prove that the açai extract is highly antioxidant, but for the packaging the values were lower than the literature. The packaging analysis for DSC proved the material resistance for high temperatures and consequently the material’s stability. It is possible to conclude that the results from this paper can be useful for future works and for food related applications, because it showed good mechanical properties, color alteration due the pH and great temperature resistance