Microencapsulation of organic pomegranate peel extract for a food circular economy: Effects of wall materials on powder functional attributes, antioxidant activity and antimicrobial property against foodborne pathogens

Abstract

In the present study, the potential of maltodextrin (MT), gum Arabic (GA), and waxy starch (WS) as wall materials for producing functional pomegranate peel extract powder (PPEP) was explored. Utilizing in vitro methodologies, this study aims to investigate the impact of different wall materials on the quality and properties of encapsulated PPEP. The organic pomegranate peel extracts, produced using 70% ethanol, were encapsulated using 10% (1:10, w/v) of the different wall materials before freeze-drying. The resulting PPEPs were characterized based on their technofunctional, physicochemical, morphological, crystallinity, antioxidant, and antimicrobial properties. The GA-encapsulated PPEP demonstrated a FRAP activity of 9 mM TE/100 g DM, which is 1.4-fold higher than the 6.40 mM TE/100 g DM observed in WS-encapsulated PPEP. Similarly, GA-encapsulated PPEP showed a DPPH radical scavenging activity of 11.21 mM TE/100 g DM, 10.7–12.6% higher than WS-encapsulated PPEP. Metabolites, including ellagic acid, punicalin α, punicalin β, and punicalagin α, were significantly higher in MT-encapsulated powder. These results establish the potential of PPEP as a natural antioxidant and antimicrobial agent for food preservation, with GA and MT as favorable wall materials. Future work will explore the synergistic effects of blending GA and MT as wall materials and assess controlled release mechanisms.