Influence of Black Mulberry Juice Addition and Spray Drying Conditions on Some Physical Properties of Ice Cream Powder

In this study, the overall quality characteristics of ice cream powders (drying yield, moisture content, water activity, bulk density, solubility and glass transition temperature) and ice creams made from their corresponding reconstituted powders (overrun, melting behavior) were analyzed. The effect of spray drying conditions such as inlet air temperature (120, 140 and 160 degrees C) and feed flow rate (1.5, 3 and 4.5 mL/min) and black mulberry juice addition (15, 30 and 45 %) were included in the design. The results showed that, by increasing inlet air temperature water activity, bulk density and overrun were decreased, while solubility and melting rate of reconstituted powders were increased. Generally, mass recovery percentage of ice cream powders was decreased with increase of feed flow rate and juice concentration at the same air inlet temperature due to the stickiness problem and the low glass transition temperature of components. The following optimum process conditions with the desirability of 0.86 were determined: inlet air temperature of 140 degrees C, feed flow rate of 1.5 mL/min and juice concentration of 30 %.