Functional polysaccharide-based film prepared from chitosan and β-acids: Structural, physicochemical, and bioactive properties

beta-Acids are natural antibacterial and antioxidant ingredients, obtained from supercritical CO2 hop extract. In this study, beta-acids/chitosan complex films were prepared using the casting method. Complex films were characterized using scanning electron microscopy (SEM), atomic force microscope (AFM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction analysis (XRD). Structure analysis revealed that beta-acids can be successfully combined with the chitosan matrix. Mechanical tests demonstrated that the tensile strength of the films showed a significant upward trend (1.9 MPa to 9.6 MPa) with increase in beta-acids content (0.1%-03%). Interestingly, the chitosan-based films showed excellent UV barrier capability below 400 nm. The release of beta-acids from the film followed Fickian diffusion (n < 0.45). In addition, the complex films inhibited the growth of five food-borne pathogens (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Salmonella enteritidis and Listeria mortocytogenes). This study highlights the promising nature of composite film as a desirable alternative for active packaging. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, beta-acids/chitosan complex films were successfully prepared and characterized. The films showed improved mechanical strength, antimicrobial properties, and excellent UV barrier capability, making them a promising alternative for active packaging applications.