Development and Characterization of the Edible Packaging Films Incorporated with Blueberry Pomace

This work focused on the development of starch-based (potato, corn, sweet potato, green bean and tapioca) edible packaging film incorporated with blueberry pomace powder (BPP). The optical, mechanical, thermal, and physicochemical properties were subsequently tested. The film color was not affected by the addition of BPP. BPP incorporated into corn and green bean starch films showed increased light barrier properties, indicating a beneficial effect to prevent UV radiation-induced food deterioration. Film thickness and transparency were not primarily affected by changing the starch type or the BPP concentration, although the corn starch films were the most transparent. Furthermore, all films maintained structural integrity and had a high tensile strength. The water vapor transmission rate of all the films was found to be greater than conventional polyethylene films. The average solubility of all the films made from different starch types was between 24 and 37%, which indicates the usability of these films for packaging, specifically for low to intermediate moisture foods. There were no statistical differences in Differential Scanning Calorimetry parameters with changes in the starch type and pomace levels. Migration assays showed a greater release of the active compounds from BPP into acetic acid medium (aqueous food simulant) than ethanol medium (fatty food simulant). The incorporation of BPP into starch-chitosan films resulted in the improvement of film performance, thereby suggesting the potential for applying BPP into starch-based films for active packaging.