Spray Drying of Prickly Pear ( Opuntia ficus‐indica [L.] Mill) Juice: Effects of Different Carriers on Yield and Powder Properties
Panagiotis Chaloulos, Athina Mourouti, Ioanna MandalaABSTRACT
Prickly pear juice ( Opuntia ficus‐indica [L.] Mill, orange variety) was spray dried with maltodextrin (MD), MD and whey protein isolate in a ratio 199:1 (WPI1), MD and whey protein isolate in a ratio 100:100 (WPI100) (1:1), MD and casein in a ratio 199:1 (Cas) and MD and gum arabic in a ratio 175:25 (GA) (7:1). The ratio of juice solids to carriers was 2:1 in all samples. Large amount of whey protein significantly increased powder yield compared to plain MD (58.47% vs. 43.17%), while the minimal whey protein addition (WPI) exhibited improved yield (49.47%) compared to plain MD. Betalains retention was high in all systems (> 90%) both for betaxanthins and for betacyanins. The retention of betalains during storage for 77 days in the dark was also good in 4°C, 40°C and 60°C, but when the powders were exposed to light in a range of relative humidity (11%–75%), the retention of betaxanthins diminished when the relative humidity exceeded 58%. Storage in relative humidity 44% or higher led to macroscopic powder caking in all systems except for the WPI100 system, in which visible caking appeared in 58% relative humidity. No substantial difference was observed in the absorption curves of the different systems. Understanding the effects and properties of each carrier is crucial when designing appropriate and cost‐effective carrier systems according to the desired properties.