The effect of the fluidized bed agglomeration process on the powder properties of black carrot juice powders

Abstract

This study aims to apply fluidized bed agglomeration process performed at 60°C and 1.6 m/s as air temperature and velocity, to improve the powder properties of the black carrot juice powders obtained by spray drying at the inlet and outlet air temperatures of 160 and 100°C, respectively. The binders maltodextrin, gum arabic, whey protein isolate and water were added to the powders at 1:0.1, and 1:0.2 powder/binder solution (BS) ratios. The agglomerates have higher moisture content (11.35%–12.88%, wet basis) and water activity (0.256–0.379) values than the powders (9.18 ± 0.03% and 0.25 ± 0.00, respectively). While the angle of repose value of black carrot juice agglomerates decreased compared to powders, the porosity values (54.17%–66.87%) and the hygroscopic properties were improved. The friability values for the agglomerates were 37.21%–77.04%. The agglomeration process improved the microstructure, glass transition temperature and particle size distribution as determined with scanning electron microscope, differential scanning calorimeter, and laser diffraction method analysis.Practical applicationsBlack carrot is a vegetable with high nutritional value and its consumption is limited to a certain season. For this reason, the production of the powders of vegetable juices and having the agglomerated form of them, an important improvement will be achieved in the production of healthy and easy to use foods for children and adults. Fluidized bed agglomeration which is a novel application is important in the creation of easy‐to‐use meals. Black carrot juice powders could be successfully agglomerated with some different binders in fluidized beds. Powder properties of agglomerates containing water were as good as the binder agents.