Materials Used for Edible Coatings, Their Characteristics and Properties

The erroneous storage and handling of biological materials result in its postharvest losses. The perishable state limit of fruits and vegetables and their span of storage owing to a combination of inherent and extrinsic variables including rates of respiration, transpiration, ethylene generation, and other environmental conditions. Among the different approaches to postharvest preservation available, edible coatings appear to be another cutting edge technique that has been demonstrated to provide a favorable and secure approach to increasing the shelf life of food items. The distinct benefits of edible coatings and films concerning synthetic films, particularly their usage as edible packaging materials, have attracted much interest recently. The rising usage of nonbiodegradable materials is harming mother earth. So, there is an urgent need for packaging materials that function as barriers and can bring down the complexity and increase recyclability. New packaging materials have been characterized from various plants and animal sources, normally considered waste materials. The edible coatings made from nontoxic biocomposites, biopolymers, and the necessity to decrease postharvest loss can be dealt with by producing edible coatings, satisfying the expanding market for sustainable packaging materials. By performing a variety of barrier properties, edible coatings guard the packaged or coated product against external chemical, physical, and biological degradation and mechanical injuries. This coating shows several applications in the production of minimally processed fruits, vegetables, or other food products and improves the quality and prolongs the shelf life. The application of these materials in food applications, especially for extremely perishable goods like horticultural ones, is dependent on several specific characteristics, including price, accessibility, functional qualities, mechanical characteristics (flexibility, tension), optical attributes (brightness and opacity), the impact of barriers against gas movement, structural durability to moisture and microbes, and sensory credibility. According to the structure, edible coatings can be made of polysaccharides, proteins, lipids or composite. Due to their intriguing potential as cutting- edge food packaging solutions, novel avenues for edible materials and processing methods are significant. Aside from these uses, there has been an upsurge to include vitamins, antioxidants, antimicrobials, nutraceuticals, and active compounds in edible coatings. This provides an improved foundation for serving as carriers of active compounds, enabling targeted release, and serving as safety and quality stimulants. The possibility for the utilization of numerous novel materials in the development of edible coatings and films has been studied by many researchers. The most crucial element in determining the ultimate functional qualities and properties of biopolymer films is the source of the biopolymer. Plant residues are easily accessible and inexpensive edible packaging supplies that are an excellent resource of nutrients. More possible uses for edible coatings that contain antimicrobials, essential oils, and other active substances are in preventing food deterioration. Despite preferential gas permeability, edible coatings have historically been utilized as a barrier to reduce water loss and postpone the inevitable senescence of coated fruits. However, the most recent type of food-grade coatings have been developed to enable the incorporation or regulated release of vitamins, antioxidants, nutraceuticals, and naturally occurring antimicrobial agents through the use of emerging techniques like layer-by-layer assembly and nano-encapsulation. The benefits of edible coatings used on food products are equally substantial. The drop in weight losses and the lengthened lifespan of food items significantly affect the expenses of food production and minimize the amount of food waste. This chapter emphasizes various materials used for edible coating and describes their characteristics and properties for better understanding.