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

p-carotene ( p C) is a liposoluble natural pigment important for human health due to their antioxidant and provita-min 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 pC 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 pC in microcap-sules 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 pC was released in the intestines with 32.78% of bioaccessibility. The release kinetics of encapsulated pC demonstrated that the pC release mechanism occurs by Fickian diffusion. The addition of pC microcapsules in cookies improved by 2-fold the antioxidant activ-ities compared to free pC microcapsules cookies. These results suggest that pC microcapsules formed by complex coacervation of OVA/NaAlg can be added efficiently in the fortification of cookies.

Automated summary

p-carotene (pC) was successfully microencapsulated using the complex coacervation of ovalbumin (OVA) and sodium alginate (NaAlg). The resulting microcapsules exhibited a spherical morphology, high encapsulation efficiency (97.90%), and release mechanism by Fickian diffusion. In vitro digestion simulation showed that 32.78% of encapsulated pC was bioaccessible in the intestines. Addition of pC microcapsules in cookies improved antioxidant activities by 2-fold compared to free pC microcapsules.