Physico-chemical, Sensory, and Antioxidant Characteristics of Olive Paste Enriched with Microencapsulated Thyme Essential Oil

In this study, thyme essential oil (TEO), a natural antimicrobial and antioxidant substance, was encapsulated by a complex coacervation method using gum Arabic and gelatin as wall material and tannic acid as a crosslinking agent. The quality characteristics of the olive paste samples, which were aimed to be increased by adding TEO (1000 mg/kg) and TEO microcapsules, were determined at 4 °C and 25 °C during the storage period of 56 days. Physico-chemical, sensory, and antioxidant activity analyses were performed on all olive paste samples during the storage period. The thymol and carvacrol contents of the enriched olive paste samples were quantified by high-performance liquid chromatography (HPLC). The enrichment of olive paste samples with microencapsulated TEO resulted in an increase in sensory properties with the total dry matter, color scores ( L *, a *, and b *), total phenolic content, thymol, and carvacrol content, while a decrease in peroxide value and total mesophilic aerobic bacteria content. The results showed that the microcapsule structure preserved TEO during storage, the antioxidant activity of olive paste samples enriched with TEO microcapsules increased, and thus, the enriched olive paste could be stored in a safer and higher quality than control samples. Therefore, using microcapsules containing TEO in olive paste samples may be a suitable method to produce functional foods with antioxidant properties.