Effect of Degritting of Phenolic Extract from Sour Cherry Pomace on Encapsulation Efficiency-Production of Nano-suspension

The objective of this study was to study the influence of purification of sour cherry pomace extract on particle size distribution of suspension and on encapsulation efficiency of powders. In addition, antioxidant activity, surface morphology, and color of powder and capsules were determined. Extraction of phenolic compounds was performed at 30 A degrees C with shaking at 70 rpm for 24 h with 1:20 solid-solvent ratio. Ethanol-water (1:1) was used as the solvent. Filtered extract was concentrated in a rotary evaporator and freeze dried to produce extracted phenolic powder (EPP). Purified extracted phenolic powder (PEPP) was obtained by degritting at 10,000 rpm for 2 min and then by freeze drying for 48 h. Purification reduced Sauter mean diameter (D ([32])) of concentrated extract from 5.76 mu m to 0.41 mu m. In encapsulation, two types of coating materials were used. The first one contained 10 % maltodextrin (MD) and 90 % distilled water, while the second one contained 8 % MD, 2 % gum arabic (GA), and 90 % distilled water. Samples were homogenized using ultrasound (160 W, 50 % pulse) for 20 min. Microsuspensions containing EPP had D ([32]) of 1.65 and 1.61 mu m when 10 % MD and 8 % MD-2 % GA aqueous solutions were used for coating, respectively. It was possible to obtain nano-suspensions when purification step was performed. Suspensions prepared with PEPP and 10 % MD and 8 % MD-2 % GA for coating had D ([32]) of 0.396 and 0.334 mu m, respectively. As a result of purification, encapsulation efficiency of the capsules increased significantly from 86.07-88.45 % to 98.01-98.29 % (P < 0.001).