Mechanical, Barrier and Morphological Properties of Biodegradable Films Based on Muscle and Waste Proteins from the Whitemouth Croaker (Micropogonias furnieri)

The objective of this work was to evaluate the mechanical, barrier and morphological properties of biodegradable films based on muscle and residue proteins from the Whitemouth croaker (Micropogonias furnieri). Protein isolate was obtained from croaker residue and myofibrillar proteins were obtained from croaker muscle. The films made with fish protein were evaluated for color parameters, opacity, mechanical properties, thickness, water solubility, water vapor permeability and morphological properties. The films were prepared by technical casting with various fish protein suspensions (3.0, 4.0 and 5.0% weight in solution). The films made with residue protein isolate (RPI) presented higher solubility than the films made with muscle myofibrillar protein (MMP). For the MMP films, the lowest protein concentration showed a lower tensile strength compared with higher concentrations of proteins. The films produced with higher protein concentration had higher water vapor permeability. Also, the RPI films had a rougher surface than the MMP films. PRACTICAL APPLICATIONS: Preparation of biodegradable films made from fish myofibrillar and residue proteins. Films with low fish protein concentration presented better characteristics. Films made with RPI had higher solubility than the films made with MMP. The increase in the protein concentrations increased water vapor permeability. The RPI films had rougher surfaces compared with MMP films. Films made from fish proteins have good strength and barrier properties.