# Edible Packaging: A Technological Update for the Sustainable Future of the Food Industry
## 3 Results
### Barrier Functions of Edible Packaging Materials  
The protective barrier effect of an edible film helps to enhance the shelf life of food products. However, in the case of vegetables and fruit, there is some degree of respiration, and it is crucial that the packaging is not completely gas, water, and ethylene barrier-proof. Edible packaging materials must meet several specific functional requirements that depend on the material type, its production, and its application. The edible films and coatings act as an environmental barrier and control the mass transfer between the food and the external environment [3]. When choosing edible materials for packaging, permeability is perceived to be a crucial consideration. The impact of moisture and temperature on film determines its intended use. Therefore, before employing it as a food packaging material, the permeability must be measured under specific circumstances [20]. For many kinds of applications, edible films and coatings should have an adequate moisture barrier. Reducing the transfer of moisture between compartments of heterogeneous food products like pizza is crucial for maintaining their various crunchy and soft textures. Variations in packaged food water activity (a\({}_{w}\)) can lead to microbiological development, deteriorating chemical and enzymatic interactions, and undesirable textural changes. Edible films and coatings with good a\({}_{w}\) gradients can significantly reduce the water migration between food compartments, thereby maintaining a crispy crust texture [21]. Water activity (a\({}_{w}\)) is a critical factor in determining the shelf life and quality of food. Water vapor barrier functions are vital for fresh produce products, such as vegetables, and are crucial to preventing dehydration in dry foods such as bread, where it is necessary to prevent moisture absorption from the environment. The amount of water vapor transmitted through a unit area, time, and pressure is known as water vapor permeability (WVP) [22; 23]. Oxygen-sensitive foods can have their shelf life extended and their quality preserved by using low-oxygen-permeability (OP) edible packaging. Additionally, the adoption of edible packaging will contribute to a reduction in the use of certain pricey and luxurious, non-recyclable, oxygen-barrier plastics. Edible films have a different range of OP values. [PERSON] et al. [24] suggested that curcumin-treated chitosan-bacterial cellulose-based films have good barrier properties like increased hydrophobicity and oxygen permeability. Starch-based films have good oxygen barrier properties due to their hydrogen-hydrogen bond structure [25]. It is important that every type of food has specific packaging requirements. For example, in the case of fruit and vegetables, packaging must not be absolutely water, gas, and ethylene barrier-proof because fruit and vegetables have a certain degree of respiration [26]. However, regarding the packaging of slices of cheese and ham, this requirement is not applicable, and the porosity should be much lower [27]. Another way to address consumer preferences and health concerns is to minimize the fat content of fried food products like potato chips with oil barrier coatings using hydrophilic macromolecules. This may cause oil barrier coatings to develop into a viable substitute for reducing oil absorption during frying. Casein-based edible films and coatings can reduce the moisture losses and cooking losses regarding meat products during frying [21]. The mechanical and barrier qualities of a coating, which are influenced by its composition and microstructure, as well as the parameters of the substrate, determine how effective it is [28]. The utilization of fluorinated oil repellents in food packaging, especially for fast food, has raised concerns due to its potential to harm humans and the environment. [PERSON] et al. [29] have presented an eco-friendly solution for the substitution of fluorine-free oil repellents, with microcrystalline wax emulsion serving as an alternative to paper-based oil repellents.