Light stability of spray-dried bixin encapsulated with different edible polysaccharide preparations

Bixin was encapsulated by spray-drying with gum arabic or maltodextrin, and the stability was evaluated in aqueous solution both under illumination or in the dark at 21 degrees C. The microcapsules containing emulsifier, such as gum arabic or maltodextrin + Tween 80, showed the highest encapsulation efficiency, respectively 86% and 75%, less superficial imperfections and higher stability than bixin encapsulated with maltodextrin alone or blended with sucrose. The kinetic behavior of bixin photodegradation in all encapsulated systems was composed by two first-order decays, due to the presence of bixin outside and inside the microcapsules. Bixin encapsulated with gum arabic was 3 to 4 times more stable than that encapsulated with maltodextrin. In all systems, greater bixin stability (< two orders of magnitude) was observed in the dark than under illuminated conditions. In addition, 10 times greater bixin stability was observed for encapsulated solutions as compared to the non-encapsulated systems in the absence of light. (c) 2005 Elsevier Ltd. All rights reserved.