Process optimization by response surface methodology for microencapsulation of pomegranate seed oil

Abstract

Pomegranate seed oil (PSO) has many health benefits due to the presence of bioactive compounds. However, higher amount of unsaturated fatty acids makes it vulnerable to oxidative deterioration. The present study focuses on optimizing microencapsulation process for quality retention of PSO using Box–Behnken design of response surface methodology. The alginate concentration and oil loading significantly affected the encapsulation efficiency (EE) and loading capacity (LC). The size, shape, and strength of the microsphere were significantly affected by the alginate concentration, oil loading, and nozzle size. Oil loading (10%), nozzle diameter (350 µm), and alginate concentration (3.23%) were optimum process conditions with resultant EE (78.03%), LC (7.83%), equivalent diameter (30.05 µm), sphericity factor (0.039), and rupture force (30.20 N). The encapsulation could reduce the increase in peroxide value (PV) and acid value (AV) by 61.45% and 48.32%, respectively, and the decrease in iodine value (IV) by 46.06% over nonencapsulated PSO during storage. Novelty Impact Statement Despite presence of various bioactive compounds and health benefits pomegranate seed oil (PSO) is vulnerable to oxidative deterioration. An optimized solution using response surface methodology (RSM) with oil loading (10%), nozzle diameter (350 µm), and alginate concentration (3.23%) could achieve encapsulation efficiency (78.03%), loading capacity (7.83%), equivalent diameter (30.05 µm), sphericity factor (0.039), and rupture force (30.20 N). Encapsulation has significantly reduced the increase in peroxide value (61.45%) and acid value (48.32%) and decrease in iodine value (46.06%) over nonencapsulated PSO during storage and thus will be useful in food, pharmaceutical, and cosmetic applications.