Optimisation of pomegranate (Punica Granatum L.) juice spray-drying as affected by temperature and maltodextrin content

Pomegranate juice powder is easier to handle and has more potential applications than the concentrate. In this study, the response surface, 3-level factorial design was used to evaluate the influence of spray-drying conditions on the physicochemical properties of a powdered product obtained by drying pomegranate juice concentrate (PJC). It was spray-dried with a lab-scale spray-dryer using 18 and 7 dextrose equivalent (DE) maltodextrins (MD) as drying-aid agents. Adding MD significantly reduced the hygroscopicity and stickiness of the pomegranate juice powder, and thus yielded higher recovery. The maximum achieved ratio of PJC/MD was 1/1, and it was obtained with the use of DE7 MD. However, graphical optimisation studies resulted in 125145 degrees C and 0.60.8 PJC/MD ratio as optimum variables to produce acceptable dried powder. The results indicated that increasing inlet air temperature increases solubility time and loss of anthocyanins and decreases bulk density and moisture content of the powder.