Encapsulation of an astaxanthin-containing lipid extract from shrimp waste by complex coacervation using a novel gelatin-cashew gum complex

In the present work, the suitability of cashew gum for forming coacervates with gelatin and encapsulating a lipid extract from shrimp waste was studied. Gelatin and cashew gum formed coacervates at pHs ranging from 4 to 4.5. They were spherical in shape and tended to aggregate and form clusters at pH 4-4.2, whereas they were formless at pH 4.3-4.5. The coacervates were able to encapsulate the lipid extract (astaxanthin encapsulation efficiency 59.9 +/- 0.01%), forming multinucleated, polymorphic microcapsules with an average size of 32.7 +/- 9.7 mu m. An accelerated stability study (43 days/36 +/- 1 degrees C/80% relative humidity) revealed an improvement in astaxanthin stability as a result of encapsulation. The microcapsules, which showed a water solubility of 28.6 +/- 4.7%, dispersed well in plain yogurt, selected as a food matrix to evaluate their coloring capacity. The color provided to the product by the encapsulated lipid extract was different in hue to that of the non-encapsulated one, showing higher chromaticity at comparable concentrations. A trained sensory panel confirmed the improvement in coloring capacity achieved through encapsulation, although no differences in odor were found. (C) 2016 Elsevier Ltd. All rights reserved.