**9.2 Edible films for packaging of dairy products**

Every day we consume dairy products, including cheese, yogurt, and milk which are an essential part of our daily diet. Among others, specifically, cheese is rich in lipids, proteins, and vitamins. Having said that, edible films regulate and control the ripening process, inhibit mass transfer, and lengthen the shelf life. Different edible casting techniques include spraying, dipping, brushing and electrostatic brushing, and casting is used to prepare film. Film covered on the cheese will increase the shelf life, brushing is normally used for small-sized cheese packaging, and for irregular shape cheese dipping method is preferred. Similarly, uniform and thin layer coating the cheese spraying method is most preferred one. On the other hand, electrostatic spraying prevents solution wastage and gives higher efficiency. Films prepared from casting technique generally create the barrier between the cheese and surrounding environment [180]. When compared to polysaccharide films, films fabricated from whey protein sources exhibit better gas barrier characteristics. As whey protein films are transparent in nature which allow consumer to see the quality of the cheese. Speaking of other dairy products, that is, butter, which contain high fat hence more found of lipid oxidation, and shelf life get reduces. To protect corn starch edible materials prepared using ginger oil stops lipid oxidation when stored at 2 to 5°C [181].

### **9.3 Edible films for packaging of fruits, vegetable, nuts, and grains**

Gas exchanges via respiration and transpiration occur during ripening and storage, as well as microbial growth, particularly molds and rots, are the main causes of fruit and vegetable deterioration [182]. Most commonly waxes, such as paraffin, beeswax, shellac, carnauba, and candellilla, are utilized as coating agents for all kinds of fruits [183]. Waxes and oils are very effective water barriers that can stop weight loss, whether they are used alone or in an emulsion with hydrocolloid or protein solutions. A thick wax layer coated on fruits significantly alters the CO2 leading to anaerobic storage that causes unequal ripening up to adulteration of fruits and vegetables [184]. Consequently, in order to have better control over the ripening, several edible films were created that increase CO2 and ethylene evaporation while decreasing oxygen penetration in the fruit. The inherent antifongic nature of the hydrocolloid employed or the incorporation of antimicrobial compounds within the film can both delay and prevent spotting. In this way, chitosan films encourage the fruit to produce the chitinase enzyme, a naturally occurring antifongic substance. Author Mazza and Qi have investigated the coatings prepared from gums, gelatin, and starch can prevent the non-enzymatic browning of peeled and blanched potatoes [185]. The bactericidal activity against *escherichia coli* (0157:H7) of apple puree-origin FFFs added with oregano, lemongrass, or cinnamon essential oils. They concluded that prepared materials have 50% bacteria killing property (0.034, >0.34, and 0.28) after incubation for 3 min at 21°C [186]. As opposed to those with carvacrol, carrot puree edible films containing cinnamadehyde have shown

*A Study on Edible Polymer Films for Food Packaging Industry: Current Scenario… DOI: http://dx.doi.org/10.5772/intechopen.107997*

#### **Figure 7.**

*Components crucial to film formation, primary traits, and uses for edible films [172].*

appreciable inhibitory activity of *Staphylococcus aureus* and *E. coli* [187]. Otoni and colleagues prepared papaya puree films blended with cinnamaldehyde nanoemulsions of various sizes. They reported all films to exhibit antimicrobial activity against *S. aureus, E. coli,* and *S. enterica* for fruits containing low preservative content [188]. Last but not least, edible films based on fruits and vegetables may also be created with unique health-promoting capabilities, such as probiotic or prebiotic films, by enhancing the market demand for sensory qualities and nutritious dietary components [189]. Therefore, applications are anticipated to be continually used in a world that is becoming more and more concerned with health-related issues. **Figure 7** summarizes the various components crucial to film formation, primary traits, and uses for edible films.

#### **9.4 Edible films for packaging of confectionaries**

Confectionary products, such as chocolates, candies, boiled sweets, toffees, and caramels, always require active packaging material which ensures protection from moisture attack, dust and dirt contaminating agents and prevents loss of sugar, fat bloom, stickiness, desiccation, and hardening. Generally, mindset is made to avoid intermixing of flavors of the various confectionary foods. In fact, milk and whey proteins, cellulose-based films, and shellac or wax lower the water and oil migrations, such as the greasy or oily feeling on fingers. Author Nelson and Fennema reported that methylcellulose films and coatings have shown lower lipid permeability which have ability to reduce fat mobility and inhibits the whitening or blooming of chocolates [190]. In comparison to the conventional confectioner's glaze, zein-ethanol bleeding employed as film-forming solution produces better results with faster drying times [126]. Author Dyhr and Sorensen have concluded that sorbitol-based coatings have ability to replace conventional sugar coatings on chewable dragees [191]. Bilayer films prepared from wax and hydrocolloid have shown improved adhesiveness which was applied on chewing gum sheets to enhance the shelf life [192].
