Effects of pretreatments on the quality of open-air and solar dried apricots

Apricots, pretreated with SO2 gas, sodium-meta-bisulfite or SO2 gas/ethyl oleate, were open-air or solar dried. Increasing initial SO2 concentrations, ranging from 3600 to 10100 mg/kg dry matter, increased the drying rates depending on the type of the pretreatment and the drying method. In the range 47-74% of the initially available SO2 is lost during drying. Hunter L (lightness) and +b (yellowness) values of SO2 gas treated-dried apricots were slightly larger than those of others. Ethyl oleate treatment, in addition to SO2 gas, accelerated both the drying and browning rates (decreasing Hunter L value). In general, Hunter +a (redness) increased upon drying of apricots.