Abstract:

Sorbic acid-loaded chitosan (CS) nanoparticles which may have a wider range of application in meat
preservation due to the superior water solubility to sorbic acid were prepared using ionic gelation process. The particle
size and encapsulation efficiency (EE) were investigated as a function of chitosan concentration, sodium tripolyphosphate
(TPP) concentration, cross-linking time, sorbic acid concentration and stirring time by single-factor and orthogonal array
designs. The CS nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR) and transmission
electron microscopy (TEM) and evaluated for release profiles in vitro. The results demonstrated that the best conditions
for preparing sorbic acid-loaded CS/TPP nanoparticles were 1 mg/mL CS concentration, 0.5 mg/mL TPP concentration,
1 mg/mL sorbic acid concentration, and cross-linking reaction for 30 min. The average particle size and EE of sorbic acidloaded
nanoparticles were 337.2 nm and 74.3%, respectively. The FTIR spectrum confirmed the encapsulation of sorbic acid by
electrostatic adsorption, and the TEM observation showed uniform particle size distribution and regular spherical morphology. The
release experiments indicated an average release of sorbic acid of 50% in 24 h, confirming its sustained release profiles.

Key words: sorbic acid, nanoparticles, optimization, characterization