Effect of matrix composition on stability, release and bioaccessibility of encapsulated folic acid

Abstract

Folic acid is a fast degradable vitamin, hence showing reducing functionality. Therefore, engineering of an efficacious vehicle for oral delivery of folic acid via encapsulation using an appropriate matrix is important. As eligible matrices, alginate and chickpea protein were compared in terms of stability, release kinetics, transport mechanism and bioaccessibility. Both matrices yielded particles of submicron-range with high encapsulation efficiency. Stability, in vitro release and bioaccessibility studies displayed reduced degradation, protection against gastric pH and increased bioaccessibility (80%) by alginate particles. The protein matrix also displayed slower release and higher bioaccessibility of folic acid compared to the free compound. Release of folic acid from alginate particles showed Fickian diffusion, while release from chickpea protein particles showed quasi Fickian diffusion and super case II transport mechanism at gastric and intestinal pHs, respectively. In conclusion, alginate particles were superior in affording thermal and photo stability, pH dependent release and higher bioaccessibility.