Quality and nutritional property changes in stored dried apricots fumigated by sulfur dioxide

Abstract

Apricots are grown in many countries and are marketed as dried or fresh. Sulfur fumigation is preferred as a low-cost pre-treatment to maintain apricot color. This study aims to determine the effect of sulfur dioxide (SO2) concentration on quality and nutritional properties of dried apricot fruits during storage. Apricot fruits were treated with different concentrations of SO2 (1,250, 2,000, and 3,500 mg·kg−1) and then stored at 20°C under 50–65% relative humidity conditions for 18 months. Fruit SO2 concentration decreased rapidly during the initial stage and then decreased at a slower rate. Fruit color darkening became more pronounced after 12 months, especially in the fruit treated with 1,250 and 2,000 mg·kg−1 SO2. After 18 months of storage, total phenolic content (839–890 mg GAE 100 g−1 dry weight), antioxidant activity (9.4–11.6 μmol TE g−1 dry weight), and β-carotene levels (42.7–47.6 mg·kg−1) of all treatments varied only slightly, despite lower values overall. Therefore, SO2 levels must be chosen based on the expected storage conditions and length of the storage period.