Desenvolvimento de filmes extrusados a base de farinha de trigo e bagaço de malte

Abstract

Population growth has led to an increase in the generation of solid waste and plastic packaging has contributed to this negative impact on the environment. In this sense, several researches are being directed to the development of biodegradable materials using starch, flours, proteins and synthetic biodegradable polymer such as poly (adipate co-butylene terephthalate) (PBAT). Malt bagasse (BM) is a by-product of the brewing industry with low added value, but it is rich in fibers and proteins, being a potential product to be incorporated in the film's formulation. This work aimed to produce films of wheat flour and PBAT added with different concentrations of BM by blow extrusion. The produced films were characterized in terms of mechanical properties, thickness, water vapor permeability (WVP), water solubility and morphology. It was possible to produce the films by blow extrusion on a pilot scale. The BM showed fiber content of 60%, and impacted directly on the properties of the films. With regard to WVP, the films showed no significant difference, suggesting that the addition of BM reduced the hydrophilicity. However, the increase in the BM concentration significantly interfered in the mechanical properties, with a reduction in elongation at break and tensile strength and an increase in Young's modulus. With the incorporation of BM, the films became opaque, with a heterogeneous, rough and yellowish surface. Among the developed formulations, film with 2.5% of BM was the one that presented properties closest to the control, indicating its potential application in the production of secondary packaging or for dry foods, also being a way to add value to a by-product and minimize the deposit of solid waste in the environment.