Bio-inspired biopolymeric coacervation for entrapment and targeted release of anthocyanin

Abstract

In order to provide stability of anthocyanin, a powerful antioxidant, encapsulant was made by utilizing two biopolymers that can be used further for the targeted release due to its intrinsic structure. Present study was carried out to encapsulate anthocyanin in coacervate employing pectin and chitosan. Entrapment efficiency of anthocyanin was evaluated in coacervates prepared in nine different combinations employing three concentration each of pectin (40, 50 and 60 mg mL−1) and chitosan (5, 6 and 7 mg mL−1) in presence of CaCl2. The developed formulation was characterised by FT-IR, XRD and SEM techniques, which clearly depicts ionic interaction between chitosan and pectin. Release pattern of anthocyanin from the coacervate followed Korsmeyer-Peppas model. The n-values calculated from the curves suggested a quasi-Fickian diffusion pattern pH 1.7 and 4.0. However, at pH 7.0, the behaviour of release was presumed to be an anomalous or case-II transport. In-vitro study revealed that bioaccessibility (%) of coacervated formulation (24.3 ± 0.5) was significantly higher than crude extract (12.2 ± 1.0) as well as purified anthocyanin crystals (18.9 ± 0.7). Better bioaccessibility of coacervated anthocyanin provided important information about its potential use in functional foods.