The effect of coating material combination and encapsulation method on propolis powder properties

Effects of coating materials on emulsion, physical (moisture content, water activity, particle density, bulk properties, wettability and product yield) and chemical (total and surface phenolic content and encapsulation efficiency) properties of encapsulated propolis, rich in bioactive substances, were investigated with two different methods (spray and freeze drying). Emulsion properties have an effect on physical and chemical properties of the final product, which varied according to the encapsulation method used and the differences in coating materials combination. These variations resulted from the differences in the heat and mass transfer mechanism of the processes. The product yield of the freeze dryer experiments was generally higher than the spray dryer experiments; since the product loss in the freeze dryer method was only due to the adhesion of the emulsions to the equipment's glass plate surface. Encapsulation efficiency varied in a narrow range for both drying methods and these results were above 95%. High microencapsulation efficiency values of powders proved that the encapsulation processes are carried out effectively. ? 2021 Elsevier B.V. All rights reserved.