Optimization of lyophilized microencapsulated phenolic extract concentration for enrichment of yoghurt and effect on chemical parameters, bioactive compounds, antioxidant activity and sensory quality under storage

Abstract

• Lyophilized microencapsulated phenolics utilized for enrichment of yoghurt. • Sensory acceptability, bioactive and chemical characteristics were compared. • Higher bioactive compounds observed in enriched yoghurt than normal yoghurt. • 2% enriched yoghurt showed higher sensory acceptance besides higher bioactives. In this study lyophilized microencapsulated phenolic extract powder (MPE) from peel of wild pomegranate fruit was utilized for enrichment of yoghurt. From different treatments, treatment (T 4 ) enriched with 2(%) MPE was found best on the basis of sensorial attributes. The significant increase ( p < 0.05) in yoghurt bioactive compounds and various antioxidant properties were observed after incorporation of 2(%) MPE. Changes in various characteristics were recorded at different storage intervals (0, 7 and 14 days). After 14 days of storage enriched yogurt retained higher phenolics (96.52%), flavonoids (97.72%), radical scavenging activity (95.85%), metal chelating activity (96.53%), FRAP (96.22%) and reducing power (94.49%) besides higher colour scores and sensory acceptability. Hence yoghurt could also be kept safe for 14 days under refrigeration temperature (4–7 °C) conditions in polystyrene cups with minimum changes in quality attributes. This study suggests that functional and antioxidant properties of yoghurt can be enhanced significantly by MPE enrichment without sensorial alterations, with maximum retention of bioactive compounds, thus product could be utilized commercially. The study also concluded that enriched yoghurt had higher phenolics and antioxidant activity which could open a new way towards the consumption of functional food.