Cold plasma pretreatment assisted whey protein isolate-gum arabic Maillard conjugates produce water-soluble microcapsules for clove essential oil release.

Clove essential oil (C) is poorly water-soluble, which limits its application in aqueous food systems. This study developed a novel strategy to fabricate microcapsules with improved water solubility by pretreating whey protein isolate (WPI) with cold plasma followed by Maillard glycation with gum arabic (GA) prior to complex coacervation and spray drying. Cold plasma pretreatment for 20 s significantly improved the degree of grafting (DG, from 22.14% to 31.92%) and emulsifying activity (from 32.88 m2/g to 52.40 m2/g) of WPI-GA Maillard conjugates (WPI-GAM). The resulting microcapsules exhibited enhanced encapsulation efficiency (86.07% vs. 80.91% for untreated), increased solubility (32.40% vs. 23.21%), and a shortened dissolution time (27 s vs. 33.5 s), while also showing sustained release of C during in vitro digestion. This work provides an efficient and mild cold plasma pretreatment-assisted glycation approach to produce high-performance, water-soluble protein-polysaccharide microcapsule wall materials for encapsulating hydrophobic bioactive compounds.