optimization of production conditions of candied apple with fruit concentrate

effect of different ratios of sucrose to fruit concentrate (orange and sour cherry), level of cacl2 (0-2%) and storage time (0-90 days) on physicochemical properties of candied apples were investigated using of a combined design. different quality indices such as total sugars content, ascorbic acid, color attribute (chroma) and overall acceptance were modeled and then multiobjective optimization were made using numerical method. optimization was based on maximization of storage time (at 2°c), ascorbic acid content, chroma and overall acceptance and minimization of moisture content. the optimum condition of candying by orange concentrate was found to be the ratio of syrup to concentrate 1:3, cacl2 concentration of 0.96% and storage time of 82 days. at this optimum point, ascorbic acid content, moisture, chroma and overall acceptance were 27.89 mg/g, 12.43%, 56.04 and 5.8, respectively. in addition, the optimum conditions for candied apples processed by sour cherry concentrate, were found in equal portion of syrup to concentrate (2:2), cacl2 concentration of 2% and storage time of 90 days. at this point, ascorbic acid content, moisture, chroma and overall acceptance were 8.75 mg/g, 12.80%, 39.32 and 8.7, respectively.