Preparation and characterization of α-galactosidase-loaded chitosan nanoparticles for use in foods

The instability of enzymes used in animal and human foods has long been an important issue in food preparation and storage. Recent breakthroughs in nanotechnology have shown the great advantages of nanoparticles (NPs) in protein encapsulation and controlled release. α-Galactosidase and chitosan (CS) were chosen as models for food enzymes and coating materials, respectively. A series of α-galactosidase-loaded CS NPs were prepared. The burst release of α-galactosidase from NPs and thermal stability of α-galactosidase after coating were tested. α-Galactosidase-loaded NPs were characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), transmission electron microscopy (TEM), photon correlation spectroscopy (PCS), and zeta potential analysis.The results were as follows:(1)α-Galactosidase was successfully encapsulated in CS NPs.(2)α-Galactosidase-loaded CS NPs had high encapsulation efficiency.(3)The thermal stability of α-galactosidase was significantly increased after loading with CS NPs.(4)The burst release efficiency of CS NPs loaded with α-galactosidase was higher than 90% at pH 3.0 and 10.0.