Influence of Sulfur Dioxide Fumigant Dose on Residues and Control of Postharvest Decay of Grapes

Sulfite residues in grapes fumigated weekly with 312 or 625 ppm did not exceed the 10 μg of sulfite per gram of fresh weight residue tolerance, whereas those with higher fumigation doses occasionally did. Commonly used commercial doses (5,000-10,000 ppm for the first fumigation followed by 1,000-2,500 ppm weekly) were higher than needed for decay control