Characterization of spray dried watermelon juice powder dried at different conditions and effect of incorporation of freeze-dried extract of papaya peel on phytochemical content of reconstituted juice

In the present investigation watermelon juice was spray-dried by varying the concentration of maltodextrin (3 and 5%) and inlet temperature (130, 140 and 150 degrees C). The physicochemical properties of the spray-dried powder of watermelon juice were studied (SWP). It was observed that moisture content, water activity, lycopene content and particle density decreased with increase in maltodextrin concentration and inlet temperature, whereas dissolution increased with increase in maltodextrin concentration and inlet temperature. The colour parameters were also affected by the maltodextrin concentration and inlet temperature. The powder (SWP with 3% maltodextrin and inlet temperature of 140 degrees C) with desired characteristics was enriched with freeze-dried papaya peel extract (FPP) at six different concentrations (0-2.5% of SWP). The results demonstrated that the total phenolic content increased and antioxidant activity increased when the concentration of FPP was increased. The desired level of FPP enrichment was found to be 1.5% based on sensory analysis.