Microencapsulation of Saffron (Crocus sativus L.) Extract in Copolymer Complexes Using Extrusion Method

Abstract

This study describes the preparation of alginate-chitosan and alginate-gel- atin beads containing saffron components to be incorporated as additives in food products. This study evaluated the influence of incorporating hydrophilic natural polymers, alginate-chitosan and alginate-gelatin on preserving saffron components. The alginate beads were coated with chitosan and gelatin as copo- lymer by extrusion method with a polyelectrolyte complex reaction between two oppositely charged poly-ions. The beads were formulated, optimized and evalu- ated to obtain high encapsulation efficiency of crocin, safranal and picrocrocin as the main components of saffron. The encapsulation variables were selected in accordance with Central Composite Design and were further optimized via response surface methodology. Alginate concentration significantly influenced particle size and encapsulation efficiency of alginate-chitosan and alginate-gela- tin beads (p ≤ 0.05). Both chitosan and gelatin positively affected encapsulation efficiency. The optimum condition for preparing alginate-chitosan beads was an alginate concentration of 1.97% and chitosan concentration of 0.925%; this yielded an encapsulation efficiency of 66.3 ± 1.5, 86.2 ± 0.7 and 52.9 ± 3% for picrocrocin, safranal and crocin, respectively. The optimum condition for preparing alginate-gelatin beads was an alginate concentration of 1.95% and gelatin concentration of 3.65%; this yielded encapsulation efficiency of 39.2 ± 2.9, 31.9 ± 1.7 and 18.3 ± 1% for picrocrocin, safranal and crocin, respectively. The results clearly indicated that, in combination with alginate, chitosan was a better copolymer than gelatin for encapsulating saffron components.