SO2-Release Performances of Sulphite Microparticles under Different Relative Humidity: SO2-Release Performance

In this investigation, the water-soluble sulphite was encapsulated using ethylcellulose phase separation and then ethylcellulose microcapsules were used as core material to prepare dual coated microparticles using melting scattered condensation method. Morphology of microencapsulation was observed by scanning electron microscopy (SEM). Release profiles of SO₂ from sulphite microparticles were also studied. The results showed that the rates of SO₂ released from microparticles were not only affected by varying the type, but also by the relative humidity in the microenvironment around microencapsulated powder, which was greatly accelerated with increasing the relative humidity.