Study of Nanoemulsified Films and Coatings for Enhanced Preservation of Minimally Processed Carrots During Refrigerated Storage

This study aimed to evaluate edible films and coatings based on carboxymethylcellulose (ECMC), alginate (EALG), and cassava starch (ECS) polymers that have been nano-emulsified by ultrasound, using food-grade sunflower oil as the lipid source and Tween 20 as an emulsifying agent. The formulations were characterized by particle size distribution, and molecular interactions in the edible films were analyzed using Fourier-transform infrared spectroscopy. Furthermore, the morphological behavior of the films was studied through scanning electron microscopy. Additionally, to assess their effectiveness as a green preservation technology for minimally processed foods, the formulations were applied as edible coatings on carrot slices, and peroxidase activity, total phenols, antioxidant capacity, and color changes during refrigerated storage were studied. FTIR spectra confirmed interactions between the compounds in the formulations of ECMC and ECS films. Instead, the spectrum of EALG was significantly similar to that of ALG, showing poor affinity between alginate and the oil in the nano-emulsion. ECS films showed a compact, smooth, and uniform surface, with oil drops inserted uniformly throughout the matrix. The biodegradable film based on ECS is considered a promising alternative for use as an edible film or coating for food preservation.