Vitamin D3 encapsulation by complex coacervation using carboxymethyl tara gum (Caesalpinia spinosa) and different proteins
tara gum, vitamin D, ultrasound, gelatin, lactoferrin, microparticles.
Vitamin D3 (cholecalciferol) is a fat-soluble bioactive that acts mainly in maintaining calcium and phosphorus homeostasis to support bone structure and its deficit can lead mainly to osteoporosis and rickets. Due to the high number of cases of vitamin D3 (VD3) deficiency, fortification of foods with this vitamin has been discussed. The vitamin's susceptibility to some environmental conditions and processing are minimized in the microencapsulation process, including complex coacervation. Microencapsulation by complex coacervation occurs mainly through electrostatic interactions between oppositely charged biopolymers, especially proteins and polysaccharides. Thus, this thesis aims, initially, to promote the insertion of a negative grouping to tara gum (TG), neutral galactomannan extracted from the endosperm of the seed of cesalpinia spinosa, and later to form complexes coacervated with gelatin A and lactoferrin to be used as material in the vitamin D3 encapsulation. The synthesis of carboxymethyl tara gum (CMTG) was studied and optimized in terms of MCA/NaOH ratio, reaction time and temperature, obtaining a maximum degree of substitution (DS) of 0.64. The formation of coacervate complexes between gelatin A and lactoferrin had an influence on pH and biopolymers ratio (Protein: CMTG) with load balance of pH 4.0 and 6:1 and 5:1 ratio, respectively. VD3 microcapsules with greater encapsulation efficiency (80%) were obtained at a total concentration of 1% and a ratio (core: wall) of 1:2 for microparticles formed from gelatin A and 1:3 for lactoferrin. The encapsulation of VD3 was able to increase the thermal etability and promote the controlled release of the vitamin during gastrointestinal simulation in vitro. This work also aimed to study the effects of ultrasonic treatment on depolymerization of aqueous solutions of tara gum in order to reduce the size of the molar mass and increase the solubility of the gum.