Porous Food Microparticles as Carriers of Lipophilic Bioactive Compounds to Improve Functionalities

Lipophilic bioactive compounds (LBCs) have been gaining attention due to their antioxidation and health-promotion properties. Although many delivery systems have been studied to encapsulate LBCs to increase stability and bioaccessibility of the LBCs, most of delivery systems lack of practicality for application in the food industry due to energy-extensive encapsulation processes and high-cost carrier materials used. Additionally, while a variety of encapsulating systems exist in nanoscale to achieve efficient encapsulation of LBCs, nanoscale systems with encapsulated LBCs may be subjected to reassessment of toxicity. In this dissertation, freeze-dried potato microparticles (FDPMs) and freeze-dried mushroom microparticles (FDMMs) were studied as carrier materials to load three LBCs: resveratrol (RSV), curcumin (CCM), and quercetin (QCT). The porous structure of both FDPMs and FDMMs provided the physical basis for use as novel carrier materials to load high concentrations of LBCs. The solutions with high amounts of RSV, CCM, and QCT were prepared in the binary solvent of ethanol and polyethylene glycol 400 (40:60 v/v) for diffusion in the porous matrix. After evaporation of ethanol, the crystalline structure of the studied pristine LBCs became amorphous after loading in FDPMs and FDMMs. Loading LBCs in FDPMs and FDMMs reduced the degradation during UV irradiation, and the amorphous state of loaded LBCs improved their solubility significant to their functionalities. The antioxidant capacity was observed for the increased ferric reducing power of RSV loaded in FDPMs and the increased DPPH scavenging activity of CCM and QCT loaded in FDPMs. The enhanced bioaccessibility than pristine RSV was observed for RSV loaded in FDPMs. The synergistic antioxidant activity was observed for CCM and QCT co-loaded in FDMMs. When CCM and QCT co-loaded in FDMMs were incorporated in beef patties, more significant inhibition of lipid oxidation than treatments with pristine ingredients was observed after cooking and refrigerated storage. Findings from the present dissertation may be significant to manufacturing functional foods to enhance the health benefits of LBCs and their utilization as natural antioxidants to improve food quality.