Development of polysaccharide networks for L-(+)-ascorbic acid stabilization into antioxidant/nutritional supplier-edible films.

ROJAS A. M.; LEÓN P. G. V.; FLORES S. K.; PÉREZ C. D.; DE'NOBILI M. D.

Handbook of Carbohydrate Polymers: Development, Properties and Applications.

Nova Science Publishers

Lugar: Hauppauge , New York.; Año: 2010; p. 393 - 418

In the past half century, synthetic petroleum-based polymers have been widely used in a variety of packaging materials but have become a major source of waste disposal problems due to their poor biodegradability. With the increasing demand by consumers for high-quality foods and concerns about limited natural resources and the environment, the use of renewable resources to produce edible and biodegradable packaging materials that can improve product quality and reduce waste disposal problems are being explored. Biopolymer-based edible films and coatings are intended to function as barriers against moisture, oxygen, flavor, aroma and oil, as well as carriers of additives thereby improving food quality and enhancing the shelf life of food products. Water-soluble polysaccharides are commonly used in food related applications as thickeners due to their increase in viscosity when hydrated. Polysaccharides can also constitute edible films, an important quality since these polymers are of natural origin and come from renewable sources and are biodegradable as well. Though it is recognized that polysaccharide edible films are not good barriers against water vapour, they can find interesting applications as food interfaces, as carriers of active compounds or preservatives, constituting delivery systems with local activity. The present chapter deals with the study of edible films based on deacylated and/or acylated forms of gellan gum to support L-(+)-ascorbic acid (AA) in view of natural antioxidant protection of foods, by leveraging its activity as a vitamin in the human metabolism. Kinetics of AA-destruction and subsequent non enzymatic browning development were studied in the films stored at constant temperature (25ºC) and relative humidity (33.3, 57.7 or 75.2%) and their relationship with the microstructure, at the macromolecular and molecular levels, was also analyzed with the purpose of ensuring a better AA retention as well as lower browning rate as a consequence of controlled water mobility in the polymeric networks.