ABSTRACT
Fresh fruits and vegetables contain considerable percentage of water, the amount of which is maintained during production in their natural environment. Respiration is maintained naturally at an appropriate equilibrium between oxygen, carbon dioxide and water by skin, which control transmission to and from surrounding environment. As soon as the fruit or vegetable is harvested, there is an increase in the respiration rate of these living tissues, resulting in metabolic loss that ultimately takes the fruit or vegetable to a gradual maturation and eventual senescence. During transit and marketing, the fruits and vegetables get bruises, in spite of the care, lose water, shine appeal and nutrients and thus require protective treatment. In fresh-cut fruits and vegetables, the wounding of tissues leads to texture breakdown, development of off-avor, and brown discoloration on the cut surface. Controlled respiration of these living tissues would improve storability and extend the shelf life of fresh and fresh-cut produce. Several techniques like controlled atmosphere (CA) storage and modied atmosphere packaging (MAP) have been used in fruits and vegetables to minimize quality changes and quantity losses during storage. Edible coatings can provide an alternative to CA storage and MAP as these coatings modify and control the internal atmosphere of the individual fruit or vegetable. Edible coatings may extend the shelf life of fresh and fresh-cut produce by regulating the transfer of moisture, oxygen, and carbon dioxide, by retaining the aroma and taste compounds in a food system, and by improving the mechanical handling property of foodstuff (Baldwin et al. 1996; Park 1999). The ideal edible coating should create a barrier that can retard loss of desirable avor
19.1 Introduction ................................................................................................................................ 363 19.2 Coatings versus Films ................................................................................................................ 364 19.3 Structural Matrix: Hydrocolloids and Lipids ............................................................................ 364 19.4 Application of Hydrocolloids Coatings ..................................................................................... 365 19.5 Application of Lipid Coatings .................................................................................................... 366 19.6 Application of Composite Coatings ........................................................................................... 366 19.7 Addition of Active Compounds ................................................................................................. 368
19.7.1 Antimicrobial Coatings ................................................................................................. 368 19.7.2 Antioxidant Coatings ..................................................................................................... 370 19.7.3 Texture Enhances .......................................................................................................... 370 19.7.4 Nutraceutical Coatings ...................................................................................................371
