DETERMINATION OF PHYSICAL PROPERTIES OF SOUR ORANGE JUICE POWDER PRODUCED BY A SPRAY DRYER

摘要

A new technique for spray drying sour orange juice using cyclone cooler and maltodextrin as drying agent was developed. A pilot-scale spray dryer was employed for the spray drying process. Sour orange juices were added with maltodextrin at 15, 25, 35and 45% before exposing to the drying temperatures at 130, 150, and 170 °C and air flow rate of 400, 450 and 500 m~3/h. the powders were analyzed for moisture content, particle size, bulk and tapped density, particle density, porosity, flowability, cohesiveness, insolubility index, angle of repose and vitamin C. The combination of maltodextrin addition and use of cyclone cooler was proved to be an effective way of product of sour orange juice powder. The results of statistical analysis of experimentaldata show that the parameters of inlet air temperature, air flow rate and use of cyclone cooler have significant effect on the product of sour orange juice powder. Also with the addition of maltodextrin, the optimum conditions have been obtained with inlet air flow of 450 m3/h, inlet air temperature of 150°C and outlet air temperature of 68.23°C.