An alkaline-trigged and procyanidins-stabilized microparticle prepared by extruding the mixture of corn starch, zein and procyanidins

An alkaline-trigged release of microparticle was prepared. The microparticle was prepared by extruding the mixture of corn starch, zein and procyanidins, and the characteristics of microparticle were detected. The 90% of procyanidins was released at the beginning in pH9 buffer solution and decreased following the chasing time. Even under the extreme alkaline condition (pH 11), approximately 50% of procyanidins was detected after 2 days chasing. The microparticle prepared by extruding the mixture of corn starch and procyanidins (SP) and microparticle prepared by extruding the mixture of corn starch, zein and procyanidins (SZP) showed high antioxidant ability, and the SP displayed five times more ABTS·+ scavenging ratio than SZP. Both of them maintained the constant procyanidins release ratio of 60% and 15% in digestive juice, respectively. The change of morphology, disintegration of crystal and breakage of chemical bonds specified the relationship between procyanidins release and damage of microparticle structure. Graphical abstract