Improving the storage quality of sweet cherry by natamycin nanoparticles/chitosan coating.

In this study, natamycin nanoparticles were prepared by anti-solvent method, and natamycin nanoparticles/chitosan coating was prepared and investigated for the preservation of sweet cherry. The results of particle size showed that the prepared natamycin nanoparticles were nano-sized, with a particle size of 209 ± 10 nm. The results of scanning electron microscope (SEM) showed that the apparent morphology was a uniform spherical structure. Fourier transform infrared spectroscopy (FTIR) proved that the prepared natamycin after the combination of Polyvinylpyrrolidone (PVP) and natamycin still had its own functional groups without new chemical bond. Compared with the control samples the solubility of natamycin increased to 1 mg/mL, leading to the enhanced antifungal activity of natamycin nanoparticles/chitosan. Natamycin nanoparticles/chitosan effectively maintained the color of sweet cherry fruits and delayed the decline of firmness, total soluble solids (TSS) and titratable acidity (TA) during storage. In particular, it effectively delayed the decay of sweet cherries, with the lowest decay rate of 10.1 %, which was 66.4 % lower than that of the control group, and there wasn't decay of sweet cherry in 35 d storage. Therefore, natamycin nanoparticles/chitosan was effectively to delay cherry fruit senescence and improved the quality of sweet cherry during the storage period.