Alginate solutions and bcarotene-loaded emulsions were then mixed together (1:1, mass ratio) for 2 h with continuous stirring to form a mixture that contained 5% oil (w/w) and either 0.5% or 1% alginate (w/w). The bcarotene-loaded hydrogel beads were prepared using a commercial encapsulation unit (Encapsulator B-390, BUCHI, Switzerland) with a 120 mmvibrating nozzle to inject the b-carotene/alginate solution into 10% calcium chloride solution. The encapsulation device was
operated under fixed conditions: frequency 800 Hz; electrode 800 V; and pressure 450 mbar. The hydrogel beads were held in the Ca2þ solution for 1 h at ambient temperature to promote crosslinking. The beads were then collected by filtration and subsequently washed with distilled water and phosphate buffer to remove any excess ions from their surfaces. The formed beads were then storage in a refrigerator so that any residual external water was removed, and then their total weight was determined.