Chokeberry (Aronia melanocarpa L.) extract loaded in alginate and alginate/inulin system

Abstract

Chokeberry (Aronia melanocarpa) is a rich source of polyphenols with confirmed health benefits. Microencapsulation tehnique is a promising tool for improving its polyphenols functionality, stability and bioavailability. Electrostatic extrusion process was carried out to obtain microbeads with encapsulated chokeberry extract. The effects of the carrier type (alginate of low and medium viscosity), addition of inulin as filler, and the needle diameter (18, 20, 22 gauges) on the morphological characteristics and release properties of the microbeads were studied. Particles obtained with medium viscosity alginate carrier (1.5% w/v), using inulin as filler (5% w/v) and medium needle size (20 gauges) showed the best results in the release studies. Drying process affected the encapsulation efficiency, the amount of encapsulated polyphenols increased from 0.24 mg GAE/g in hydrogel beads to 3.57 mg GAE/g in freeze dried beads, and the release profile of encapsulated extracts was prolonged to 40 min. SEM micrographs confirmed that the addition of inulin as filler improved the final properties of the microbeads, while FTIR analysis showed that the extract was successfully incorporated into the particles. Due to the extended storage and stability, dry microbeads showed the best potential as a delivery system suitable for pharmaceutical or functional food industry.