Native and modified starches as matrix for edible films and covers

Among the natural n-polymers for to elaborate edible films is the starch. Though, it by itself can not to develop the satisfactory functional properties to produce an adequate film. Native starches have several drawbacks associated to their hydrophilic properties that limit its function as barrier The plasticizers, improves the characteristics and properties of the films, in addition it has been used native starch reinforced with non- starchy components, as palliative. However, a best solution could be the use of modified starch, which help them to reach those barrier properties that making them applicable to the function desired. Films from cross linked starch tend to be permeable to water vapor and have higher hydrophilic properties, which increased its thickness, permeability, solubility, and stability in acidic and alkaline medium. Acetylated starch- based films shown stability to the decomposition by temperature, but are sensible to degradation. Starch dual modified have produced films with strong tensile strength, elongation at break and solubility, while the transparency value decrease. The sequence of duality of modification procedure also has impact on the structure of the films. The chapter complicates and discusses the aspect regards to the use of modified starch as matrix for to produce films and coating