Application of functional edible films with antioxidant, probiotic, and antimicrobial properties on Mexican sweet potato candy

Abstract This study aimed to develop composite functional edible films based on fermented (Lactobacillus acidophilus) or nonfermented whey solution, prebiotics, and/or dragon fruit (DF) powder. Edible films were assessed in their physicochemical, mechanical, antioxidant, probiotic survival, and antimicrobial (Salmonella Typhimurium) characteristics after 30 days of storage (4 °C). A selected edible film was applied to improve the quality characteristics of Mexican sweet potato candy (camote de Puebla). The fermentation process reduced the pH and increased the acidity of edible films, without affecting their mechanical characteristics. Adding DF affected the colour of edible films, increasing their total phenolic compounds (63%–288%) and antioxidant capacity (46%–163%). After storage, the probiotic count was maintained [>1×107 Colony Forming Units (CFU)/g)] in edible films based on fermented solutions, showing antimicrobial activity. Selected edible film enhanced the functional properties of sweet potato candy. However, colour and appearance were negatively affected, especially after 15 days of storage.