Effect of Type and Concentration of Carrier Material on the Encapsulation of Pomegranate Peel Using Spray Drying Method

Foods. 2021 Aug 24;10(9):1968. doi: 10.3390/foods10091968.

Abstract

This study aimed to establish a procedure for pomegranate peel (PP) valorization and attainment of stable extracts with preserved bioactive compounds. The technology applied was spray drying with carbohydrate-based (maltodextrin, MD) and protein-based (whey protein, WP) carrier materials in different concentrations (80, 100, and 120%). What was analyzed was the impact of the type and concentration of carrier material on the stability and quality of the final encapsulated powder. The best results were achieved when the PP extract was microencapsulated with the carbohydrate-based carrier (100%), where it had the highest encapsulation efficiency (EE) (88.63%), hygroscopicity (15.17%), and water solubility index (87.04%). The moisture content was in the range of 3.69-4.60% and 4.21-5.84% for MD and WP, respectively, indicating that both are suitable for long-term storage. It was observed that changes in carrier concentration significantly influenced most of the powders' physicochemical properties. Microencapsulation using MD yielded a higher content of punicalin, punicalagin, gallic, and ellagic acid than those with WP. Overall results demonstrated that carbohydrate-based microencapsulation can be utilized efficiently for the protection of powder stability and phytochemical characteristics.

Keywords: Punica granatum; maltodextrin; polyphenols; pomegranate peel; spray drying; whey protein.