# Processing Fresh-Cut Potatoes Using Non-Thermal Technologies and Edible Coatings
## 5 Emerging Processing Technologies: Operating Principles and Examined Parameters
### Edible Films and Coatings  
Edible films and coatings can be used as barrier layers to oxygen and carbon dioxide, as well as carriers of antioxidant or antimicrobial agents, to extend the shelf life of fresh food against oxidation and microbial spoilage [220,221]. Polysaccharides, proteins, and lipids derived from agricultural feedstocks (maize, wheat, potato, cassava, soy bean) are the main ingredients used to produce edible films and coatings [222,223]. Natural biopolymers for the production of edible films and coatings can also be recovered by valorizing waste from food processing, contributing to the concept of circular economy [220]. Edible coatings have been applied to fresh-cut vegetables and fruits as an immersion solution, whereas edible films in solid sheet form are wrapped around the product [220]. The mechanical properties, transparency, and oil resistance of polysaccharide films are better than those of protein-based films [223]. On the other hand, protein films exhibit lower water transmission [223]. Lipid films (fatty acids, beeswax) are fragile but more hydrophobic, reducing water permeability [223]. Alginate, chitosan, pectin, carrageenan, and starch are the most abundant polysaccharides in nature after cellulose and are mostly used as edible coatings of fresh-cut vegetables and fruits [49,220]. Polysaccharides can be extracted from microorganisms, algae, and crustacean cells (shrimps, crabs), as well as from the fruits, stems, and clades of wild or cultivated crops [49,162,220]. Recently, there has been an interest in extracting polysaccharides from cladodes, which are flattened leaf-like stems in cactus genera such as _Opuntia_ sp. [162,215]. The biomacromolecules of polysaccharides, consisting of arabinose, xylose, fructose, glucose, galacturonic acid, and rhamn, exhibit antioxidant and antibacterial activities [162,215]. Polysaccharide films, in native or modified form, are functional and promising materials to employ in food preservation as active packaging [224]. The modification of edible films can be achieved via salt pretreatment, esterification, etherification, ozonation, electron beam irradiation [225], and impregnation of nanoparticles [224] or antimicrobial/antioxidant proteins [221]. For example, the treatment of alginate with calcium (CaCl\({}_{2}\)) produced a flexible and water-insoluble biopolymer [49]. Bioplastics produced from starch and other renewable resources are proposed as an alternative to non-biodegradable plastics, which are accumulated in the environment [221]. The addition of plasticizers such as glycerol to raw starch is necessary to improve the thermal, physical, and microstructural attributes of edible films, giving them thermoplastic properties [221]. On the other hand, the incorporation of antioxidant and antimicrobial agents, such as metal nanoparticles (selenium) or proteins (lactoferrin, lysozyme), in low concentrations makes starch-based films an active packaging material [221; 224]. Organic or inorganic active compounds can be released into the food from the biodegradable film, augmenting the preservation efficiency [221]. Additionally, the application of proteins and nanoparticles to fresh-cut potatoes, either incorporated in edible films or used in dipping solution, is a novel research topic. In addition, consumers show a greater preference for natural agents such as essential oils [211], plant extracts [192], polysaccharides [162], and probiotic microbial strains [191]. Recent research on edible coatings as preservation strategies for fresh-cut potatoes highlights the effectiveness of natural anti-browning and antimicrobial agents in extending shelf life. Essential oils, such as rosemary essential oil (REO), combined with antioxidants like ascorbic acid (AA), have shown substantial promise. For instance, edible coatings formulated from polysaccharides, like those derived from potato peels, create protective barriers that maintain quality by reducing enzymatic browning, minimizing microbial growth, and preserving texture over extended storage periods [64].