Sulfur dioxide (SO2) is a gaseous preservative. It enters into the microorganism cell through microbial cell membrane. It stops the important bioorganic process in micro-organism. It reacts with nucleoside, co-enzyme and pyridine base of cells and destroy the micro-organism.
Sulphur dioxide is widely used in the food and drinks industries for its properties as a preservative and antioxidant. Whilst harmless to healthy persons when used in recommended concentrations. The health risks of sulfur dioxide in dried fruits. Dried fruit can cause respiratory problems if you have sulfite sensitivity.