Optimization and Evaluation of Bioactive Characteristics of Commercial Rumex abyssinicus (Mekmeko) Tea in Ethiopia

The physicochemical parameters, mineral composition, and nutraceutical properties of commercial “mekmeko” teas powder were analyzed in the present study. The pH of samples was slightly acidic (3.74 to 4.15), titratable acidity was low (0.094 to 0.155%) and sensory attributes (over all acceptability) were wide variable (5.9 - 6.69). The optimized selected commercial “mekmeko” tea obtained pH(4.05), titrable acidity(0.069%) ,acceptable sensory results (6.69), acceptable highest content of zinc (0.069 mg•L−1), magnesium (2.12 mg•L−1), potassium (62.34 mg•L−1),iron (0.28 mg•L−1) and calcium (17.19 mg•L−1). The nutrceticual property of optimized commercial “mekmeko” tea obtained acceptable highest content in total phenols (211.38 mg•L−1), total flavonoids (62.98 mg•L−1), total catechins (409.67 mg•L−1), and total anthocyanins (581.97 mg•L−1). Optimized “Mekmeko” teas showed the highest antioxidant capacity levels in DPPH (718.41 μmolTE•L−1), ABTS (607.62μmolTE•L−1), and FRAP (953.81μmolTE•L−1) assays. The results obtained in the present work give information to consumers for choosing flavored-colored ready-to-drink “mekmeko” tea based on the physicochemical, nutritional and nutraceutical properties.