Improved Sulfur Dioxide Fumigation of Grapes Loaded in Railway Refrigerator Cars

Excerpts from the report: This report describes an important phase of the Department's research program on reducing post-harvest decay losses and maintaining quality in fresh table grapes. Effective fumigation of grapes in railroad refrigerator cars is necessary to prevent spoilage in transit and during marketing, and also to prevent injury to the fruit. All California and Arizona table grapes are fumigated with sulfur dioxide before shipment, to prevent decay. Improved methods of circulating the air in refrigerator cars to disperse the gas quickly and uniformly through the load are given in this report. If dispersal is slow or uneven, as is common in commercial practice, underexposure or overexposure results. Underexposure would allow decay to develop, and high concentrations of gas can severely damage the grapes.