Influência da adição de pó rico em colágeno nas propriedades físicas, ópticas e mecânicas de biofilmes à base de celulose microfibrilada

Abstract

The increasing production of plastics for packaging has significantly contributed to the accumulation of waste on a global scale, driving the search for sustainable alternatives. In this context, animal by-products stand out as promising sources for the development of biodegradable coatings, especially chicken feet, which have a high concentration of collagen with relevant functional and technological properties. Therefore, the objective of this work was to incorporate microfibrillated cellulose (MFC) and glycerol into a collagenrich product extracted from chicken feet, aiming at the formation of a biodegradable coating. The mechanical and functional properties will be evaluated to assess the material’s potential to replace synthetic packaging. Based on the Box-Behnken experimental design, the process was evaluated with three independent variables: the concentration of Collagen-Rich Powder (CRP), the number of cycles in the Masuko mill (NP), and the concentration of glycerol (GL). The response variables evaluated were Roughness (ml/min), Modulus of Elasticity (MPa), Tensile Strength (kN/m2), Elongation at Break (%), Density (kg/m³), Transparency (R), Opacity D65 and Opacity C. It was found that the proportion of PRC in the biofilm formulations was the factor that had the greatest impact on the mechanical, physical, and optical properties of the developed biofilms, resulting in greater rigidity and fragility, since it presented lower values of elongation at break (0.54%) and tensile strength (0.35 kN/m²) and higher values of modulus of elasticity (up to 6924.25 MPa), density (up to 1917.85 kg/m³), and opacity (up to 43.12). The results showed a typical behavior of denser and more structurally organized polymeric systems, related to the intrinsic characteristics of PRC, which contributed to the self-assembly of the triple helix and the formation of stable intermolecular networks. Thus, the results demonstrate technical viability for process optimization and for the application of collagen-based biofilms as edible and sustainable coatings.