Development of Microcapsules Containing Water and Lipid Soluble Natural Colorants for Trout Pigmentation

Abstract

Microcapsules containing water and lipid dispersible natural colorants were formed using as wall materials mesquite gum and gum arabic. The theoretical total pigment concentration of the microcapsules was 4.6 g/kg. Spectrophotometric measurements indicated that the microencapsulated pigments underwent zero order degradation kinetics, and that mesquite gum provided the pigments a better protection than gum arabic. Mesquite gum microcapsules complied with the requisite of exhibiting a pigment degradation of less than 10% during 6 months, while the gum arabic microcapsules did not. Likewise the chromatic parameters a, b and L experienced zero order kinetics decrease, which was more pronounced for the gum arabic microcapsules. The superior protection provided by mesquite gum is attributed to the thicker adsorbed polymer layers of the microcapsules due to its higher molecular mass as compared to that of gum arabic. Trouts fed diets containing the microcapsules for three weeks acquired muscle pigmentation similar to the color exhibited by the natural colorant blend in the microcapsule, establishing the feasibility of employing these microcapsules in fish pigmentation.