Drying of apricot slices using osmotic dehydration process (sucrose - salt solutions)

Osmotic drying process is application of hypertonic solution (osmotic) for the disposal of water from the product. The aim of this study was investigation on the different concentrations of osmotic solution, different temperatures and times of treatment for drying of apricot and chooses the best treatment. Water loss (WL %) and solid gain (SG %) at different temperatures and three different osmotic solutions (sucrose-salt) for 5 hours were used to choose the best osmotic treatment to produce dried apricots. The used treatments were including of different osmotic solutions (sucrosesalt %55-5, %50-10 and %45-15, respectively) and different temperatures (at 50°C and 60°C) during 5 hours (1, 3 and 5 hours). The results showed that the best treatment among the 18 different treatments was the treatment containing osmotic solution of %50 sucrose and %10 sodium chloride and treatment time of 5 hours at 60°C with respect to the lowest SG/WL which made better drying of apricots in comparison with the other treatments and was known as the best treatment. Among the measured parameters, the lowest solid gain and the highest water loss were related to treatment containing osmotic solution of %55 sucrose and %5 sodium chloride and treatment time of 5 hours at 50°C and the treatment containing osmotic solution of %55 sucrose and %5 sodium chloride and treatment time of 5 hours at 60°C, respectively. The results showed that among the three different osmotic solutions, the dried samples with solution 1 (sucrose-salt with %55-5) and solution 2 (sucrose-salt %50-10) had the highest amount of total sugar. The highest and the lowest amount of vitamin C were related to the dried samples with the osmotic solution 1 (sucrose-salt 55-5%) (8.75mg /100g) and the osmotic solution 3 (salt sucrose- 45-15%) (7.39 mg/100g), respectively. The results showed that vitamin C content was significantly (P0.05) except in the flavor.