Ovalbumin and sodium alginate complex coacervates as delivery system of β-carotene: Formation, characterization, and cookies fortification

β-carotene (βC) is a liposoluble natural pigment important for human health due to their antioxidant and provitamin A activities but presents high chemistry instabilities which increases their oxidation in the presence of light, oxygen, high temperatures and low pHs. This research aimed to microencapsulate βC by complex coacervation of ovalbumin (OVA) and sodium alginate (NaAlg). The microencapsulation technique was employed at pH=4.0 and 8:1 OVA/NaAlg (w/w) ratio, after confirming their affinity with zeta potential, state diagram, turbidity, and isothermal trituration calorimetry analyses. The obtained microcapsules presented spherical morphology with well-defined core and high encapsulation efficiency (97.90%). The presence of OVA, NaAlg and βC in microcapsules was confirmed by the Fourier transformed infrared analyses. The in vitro simulation of the gastrointestinal digestion of the microcapsules revealed that 71.39% of microencapsulated βC was released in the intestines with 32.78% of bioaccessibility. The release kinetics of encapsulated βC demonstrated that the βC release mechanism occurs by Fickian diffusion. The addition of βC microcapsules in cookies improved by 2-fold the antioxidant activities compared to free βC microcapsules cookies. These results suggest that βC microcapsules formed by complex coacervation of OVA/NaAlg can be added efficiently in the fortification of cookies.