Chevon Meat Storage Stability Infused with Response Surface Methodology Optimized Origanum vulgare Leaf Extracts

Abstract

The present study was planned to optimize the extraction protocol to obtain the antioxidant-rich bioactive extracts from Origanum vulgare leaves. Box–Behnken design (BBD) was used with three different variables, viz. extraction temperature (70–85 °C), extraction time (5–15 min.) and solvent concentration (55–65% aqueous ethanol). Antioxidant efficacy of the extracts was recorded by evaluating four responses, viz. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), Superoxide anionic scavenging activity (SASA) and total phenolic contents. Optimized model predicted solvent concentration of 60% with an extraction time of 10 min and extracting temperature of 75 °C with a higher yield of bioactive-rich extracts. Efficacy of obtained bioactive-rich oregano leaf extracts (OLE) subjected for in vitro evaluation in chevon emulsion stored at 4 ± 1 °C for 9 days by evaluating various physico-chemical, microbiological and sensory quality characteristics. The pH was significantly (P < 0.05) higher in control than all treatments groups, and aw showed decreasing trend throughout storage period. Microbiological quality and oxidation efficacy values, viz. Thiobarbituric acid reactive substances (TBARS), Peroxide value (PV) and FFA followed an increasing (P < 0.05) trend throughout the storage period of 9 days irrespective of added level of OLE, showing better microbial stability and lowest oxidation in samples treated with 1% OLE. Sensory scores were higher in OLE-treated samples than control. It is concluded that extraction of bioactive antioxidants from Origanum vulgare leaves could be improved by optimising extraction parameters using RSM. Origanum vulgare leaf extracts incorporation at 1% level showed potential to be used as novel natural antioxidants in chevon emulsion.