Effect of microencapsulated thyme (Thymus vulgaris) essential oil on the antimicrobial and physicochemical properties of starch food packaging

This research endeavoured to explore the potential application of thyme essential oil (TEO) in the production of cassava starch (CS) films for active packaging. The study incorporated TEO both in its unencapsulated form and encapsulated through complex coacervation into the cassava starch film. The antimicrobial properties of the resulting films were assessed. The control films and those exhibiting antimicrobial activity were subjected to extensive physicochemical characterisation, including measurements of thickness, mechanical properties, visual analysis using atomic force microscopy (AFM), colour, luminosity, opacity, Fourier transform infrared spectroscopy (FTIR), moisture content, solubility, and vapour transmission. The outcomes indicated that the presence of TEO, whether in its unencapsulated or encapsulated form, significantly affected the roughness of the CS films, reducing their solubility and enhancing their hydrophobicity compared to the control. It was also observed that unencapsulated TEO negatively impacted the films' integrity, whereas encapsulated TEO displayed a synergistic effect with CS films, improving their barrier properties and suggesting their potential use in food packaging applications.