Co-loading curcumin and quercetin in freeze-dried mushroom microparticles to inhibit lipid oxidation in beef patties

Curcumin (CCM) and quercetin (QCT) are natural antioxidants. In this study, the two antioxidants (5:1 w/w) were loaded into freeze-dried mushroom microparticles (FDMMs) to achieve synergistic antioxidative effect, and CCM-QCT-loaded FDMMs were incorporated in cooked beef patties to inhibit lipid oxidation. The loading was done by diffusing CCM-QCT dissolved in ethanol and polyethylene glycol-400 (40:60 v/v) into FDMMs. The loading capacity was 4.3% and 1.3% (w/w) for CCM and QCT, respectively. Crystalline CCM and QCT became amorphous within FDMMs according to X-ray diffraction and scanning electron microscopy. Confocal laser scanning microscopy confirmed the diffusion of CCM and QCT into the intracellular matrix of FDMMs. Both CCM and QCT were effectively preserved within FDMMs during UV irradiation at 253 nm. The minimum 2-thiobarbituric acid reactive values were observed for the patties with CCM-QCT-loaded FDMMs. Our results demonstrate the potential of porous mushroom matrices for loading lipophilic antioxidants to improve food quality.