Reducing pungency and enhancing water solubility of paprika oleoresin: a study on co-crystallization and ionic gelation

Paprika oleoresin is a dark red, oily, water-insoluble, light-sensitive, and heat-resistant liquid. Paprika oleoresin may cause irritation in the mouth and stomach due to the capsaicinoids it contains. Encapsulation of oleoresin and its capsaicinoids might help reduce stomach upset and burning sensation felt in the mouth followed by discomfort in the stomach after ingestion. The total capsaicinoid content of oleoresin in dried paprika (cultivar Sena) was 300,558 mg/kg oleoresin with a Scoville Heat Unit (SHU) of 4,838,992. The paprika oleoresin was encapsulated by co-crystallization and ionic gelation techniques. The encapsulation efficiency was between 36.63 and 64.11% for alginate capsules, while higher efficiency values, between 67.03 and 85.06%, were obtained for co-crystal capsules. The yield was also higher for co-crystal capsules (79.17–85.28%) than alginate capsules (43.46–67.63%). Higher scores were obtained for alginate capsules compared to co-crystal capsules in terms of total phenolics, flavonoids, carotenoids and antioxidant capacity. Sensory analysis showed that the orally perceived pungencies of the capsules, SHUs varied between 41,641 and 2,647,022, were significantly (p < 0.05) reduced compared to the pungency of oleoresin. The capsules with reduced pungency might be a suitable ingredient for consumers displaying sensitivity to pungent oleoresin after consumption.