INFLUENCE OF ULTRASONIC TREATMENT ON THE MECHANICAL AND SURFACE PROPERTIES OF POTATO STARCH-BASED FILMS WITH VARIOUS GLYCEROL CONTENT

Starch-based films are suitable for applications such as single-use food packaging for products with a short shelf life, offering a potential green alternative to certain plastic packaging materials. Although starch-based films offer suitable gas barriers and optical properties for packaging applications, their poor moisture resistance and mechanical strength limit broader use. Ultrasonication presents a promising and efficient solution to these challenges, offering high effectiveness, environmental sustainability, and safety. Selected properties of potato starch-based films with or without ultrasonication were investigated. To explore the impact of glycerol (GLY) content and ultrasonication on starch-based films, a series of films with varying concentrations of glycerol (ranging from 20% to 80%) were developed. The resulting films were characterized by tensile properties, water contact angle (WCA), Fourier Transform Infrared Spectroscopy (FTIR), surface roughness, and Scanning Electron Microscopy (SEM) techniques. It was observed that the application of sonication treatment had both positive and negative effects on the films' overall characteristics. Specifically, the tensile strength values increased by 20% following ultrasonication treatment, particularly in films containing 20% and 40% GLY. Furthermore, the values of WCA increased, indicating slight hydrophobization of the film surface. Finally, the SEM images confirmed the smoothness of the film surface. It was found that ultrasound treatment can improve the overall film performance.