Development of β-Carotene Microcapsules with Enhanced Bioaccessibility and Physicochemical Stability as Colorants for 3D Printing

Abstract

β-Carotene was always susceptible to adverse effects under environmental stresses, such as oxygen, heat, light, and acidic pH treatment. Herein, β-carotene microcapsules with enhanced bioaccessibility and physicochemical stability were fabricated as colorants for 3D printing. To achieve this goal, the effect of combined antioxidants with diverse polarities and concentrations, including α-tocopherol (TOC, 3.3 ~ 11.7 wt%), ascorbyl palmitate (AP, 1.98 ~ 7.02 wt%), and sodium ascorbate (SA, 4.64 ~ 11.36 wt%), on the physicochemical stability and bioaccessibility of β-carotene microcapsules, was investigated. The response surface methodology (RSM) results expounded that the antioxidant levels along with two response variables (storage degradation rate and photolysis half-life of β-carotene) were well fitted with high accuracy. Both storage and photolysis stability of β-carotene were enhanced by raising the antioxidant levels while excessive TOC and AP might reversely boost its degradation. The optimized formula of AP, TOC, and SA was 4.467%, 6.610%, and 8.815%, respectively. In this case, the storage degradation rate and photolysis half-life of β-carotene were 19.09% and 4.46 h⁻¹, respectively, and the resulting β-carotene microcapsules exhibited lower cis-isomer ratio (11.05%), higher loading rate (20.58%), and bioaccessibility (4.18%). Furthermore, when used as colorants in 3D printed pomelo purees, β-carotene microcapsules exhibited strong tolerance against thermal degradation and color fading during streaming treatment.