Quality Evaluation of Tea Brewed from Blends of Soursop (Annona muricata) and Moringa (Moringa oleifera) Leaves

Abstract

Tea is commonly made from the leaves of Camellia sinensis. Production of similar drinks from other plant leaves with potential health benefits would help to prevent diseases. This study examined the chemical composition and antioxidant activity of tea made from blends of dried moringa (Moringa oleifera) and soursop (Annona muricata) leaves. Mature, fresh and green leaves from both plants were washed in water and sun-dried for 10 h. The dried leaves were milled and sieved to obtain the tea powders. Blends of soursop: Moringa tea were formulated as follows: A: 100% Soursop, B: 100% Moringa, and soursop: Moringa blends as C:50:50%; D: 60:40% and E: 40:60%. Ten grams of each blend of tea powder was brewed in 100 ml of hot water (90°C) for 10 min and cooled to room temperature (28 ±- 2°C) before analysis. From the result, 50:50 soursop-moringa tea gave the highest levels of vitamins C and A. Mineral levels were significantly different among the samples (p<0.05) with higher values recorded for calcium (2117.10 mg/100 ml), sodium (146.02 mg/100 ml), magnesium (362.03 mg/100 ml), phosphorous (241 mg/100 ml), zinc (7.13 mg/100 ml) and potassium (1207.20 mg/100 ml) in 50:50 soursop-moringa tea. The pH differed significantly (p<0.05) in all the tea samples and ranged from 7.28–7.81. Total solids gave values ranging from 3.47 mg/l-3.82 mg/l (p˂0.05) and total sugars 1.12–3.07% (p<0.05). The amount of tannin was significantly higher (p<0.05) in all tea blends compared to other antinutrients analyzed in this study and ranged from 8.95-9.84%. Assessment of the antioxidant capacity by Diphenol-2,2picrylhydroxyl (DPPH) and Ferric reducing antioxidant power (FRAP) showed significant differences (p<0.05) among the tea samples with the 50:50 soursop: Moringa blend having the highest antioxidant activity with values up to 89.04% and 531.44 (µM/L) in each case. Overall the soursop-moringa tea blends exhibited good chemical composition and antioxidant activity, with 50:50 formulation showing the best nutritional quality attributes.