Storage quality of “Red Globe” table grape ( Vitis vinifera L.): Comparison between automatic periodical gaseous SO 2 treatments and MAP combined with SO 2 pad

Many researchers have studied the application of SO2 in fruit preservation, and most studies focused on using modified atmosphere packaging (MAP) + SO2 pads that are being widely used in commercial table grape storage. We introduced an automatic and periodical SO2 fumigation device in this study, by which we could accurately set and control SO2 concentration and treatment duration. The aim of this study was to compare effects of traditional MAP + SO2 pad and periodical SO2 fumigation on storage quality of "Red Globe" table grape (Vitis vinifera L.). Results suggested that MAP + SO2 pad became less effective to inhibit fungal pathogens during late storage period, whereas 0.1 ml/L and 0.3 ml/L × 30 min SO2 fumigation every 30 days was able to maintain the storage quality of "Red Globe" table grape for 240 days. Practical applications An automatic and periodical SO2 fumigation device was designed and applied to "Red Globe" table grape (Vitis vinifera L.) in this study. 0.1 ml/L and 0.3 ml/L × 30 min SO2 fumigation every 30 days are fit for long-term storage of "Red Globe" table grape which could significantly reduce SO2 residue and improve the storage quality compared with MAP + SO2 pad.