Thermophysical properties and antioxidant capacity of spray-dried curcumin multilayered microcapsules stabilized by gelatin, gum arabic and tannic acid

The use of curcumin in different food products is restricted due to its poor water solubility and chemical instability. In this context, to facilitate the incorporation of curcumin in food products and increase its protection against light, the study was aimed at developing spray-dried curcumin multilayered microcapsules stabilized by gelatin, gum arabic, and tannic acid, characterizing their thermophysical properties, and studying the antioxidant capacity of microencapsulated curcumin and storage under light conditions. Spray-dried curcumin multilayered microcapsules were prepared and characterized by particle size distribution, Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FT-IR) spectroscopy, Differential Scanning Calorimetry (DSC), and antioxidant capacity. The volume mean diameter D (4.3) of the microcapsules stabilized with one (gelatin), two (gelatin + gum arabic), and three (gelatin + gum arabic + tannic acid) layers was 106.44 (14.80), 22.83 (0.59), and 41.74 (2.30), respectively. The microcapsules exhibited a semi-spherical shell structure, and the governing forces between microcapsule components were electrostatic, hydrophobic, and hydrogen bonding interactions. The addition of wall materials increased the glass transition temperature (Tg), which allowed that two- and three-layered preserved the antioxidant capacity of curcumin under light conditions, holding great promise for this approach in the application to other lipophilic bioactive compounds.