This research was carried out in the Department of Food Sciences - Faculty of Agricultural Engineering, Damascus University. This research was conducted with the aim of manufacturing hot air dried persimmon leather using different treatments and manufacturing persimmon puree powder by adding drying aids (maltodextrin and gum arabic) at different concentrations with the addition of tricalcium phosphate as an anti-caking agent and using two drying methods (hot air and lyophilization), manufacturing osmotically dried persimmon slices using different initial treatments, and demonstrating the effect of these treatments on the chemical, physical and color indicators, sensory properties, content of biologically active compounds and antioxidant activity of the resulting dried persimmon products during storage for six months at room temperature. The samples of hot air dried persimmon leather with (starch + maltodextrin) added maintained the highest content of total phenols, beta-carotene, vitamin C, and antioxidant activity estimated by (DPPH and FRAP) methods. The powders manufactured by adding maltodextrin at a concentration of 45% were characterized by higher yield, solubility, bulk and true density, total phenols, beta-carotene, vitamin C, and antioxidant activity according to (DPPH and FRAP) methods, while it had the greatest significant effect in reducing the degree of caking, hygroscopicity, total moisture, and total tannins, while the powders manufactured by adding gum Arabic showed an increase in their content of ash, total acidity, and potassium. The hot air drying method was superior in yield, bulk and true density, total phenols content and antioxidant activity according to the DPPH and FRAP methods, and was characterized by the lowest values of degree of caking, while the lyophilization method was characterized by the high content of total moisture, total sugars, vitamin C, beta-carotene, powder solubility, and the lowest values of hygroscopicity. The samples treated with sucrose solution (60%) were superior in their content of total sugars, total phenols, vitamin C, and antioxidant activity, while the samples treated with sugar solutions and added calcium chloride showed a remarkable superiority in the total acidity percentage, their content of biologically active compounds, and antioxidant activity. The samples of hot air dried persimmon leather with (starch + maltodextrin) added, the juice samples prepared with 30% gum Arabic and dried using lyophilization, the juice samples prepared with 45% maltodextrin and dried by hot air, and the samples of persimmon slices treated with (sucrose 40% + glucose 20% + calcium chloride 0.12%) solution had the highest sensory acceptance, as the studied characteristics (taste, texture, color, final acceptance degree) were the best for these products.
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Keywords: Fresh persimmon fruits, Leather, Powder, Slices, drying aids, Chemical and Physical Indicators, Biologically Active Compounds, Antioxidant Activity, Solubility, Degree of caking , Hygroscopicity, Flowability, Sensory Properties.
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