Comparative Study of Mineral Content in Different Varieties of Green Tea

Abstract

Camellia sinensis L. leaves composed of different concentrations of mineral contents play a vital role in human nutrition and health. In this study, locally processed three different green tea varieties i.e. P3, P5 and P9 were used for mineral content determination at National Tea and High Value Crops Research Institute (NTHRI), Shinkiari, Mansehra, Pakistan. Atomic absorption spectrophotometer, flame photometer and Kjehldal apparatus were used for the determination of mineral concentration in all the collected tea samples. Mineral composition of tea samples were identified in the following quantity order: high level of nitrogen (37300 to 41380 mg/L), calcium (515.6 to 522.1 mg/L) and phosphorus (742 to 1220 mg/L) were observed in all tea samples compared to other minerals. Cobalt (Co), molybdenum (Mo), sodium (Na), zinc (Zn), nickel (Ni) and copper (Cu) were highest in P3, while least amount was identified in P5, variety. On the contrary, calcium (Ca), potassium (K) and lead (Pb) contents were maximum in P5, while minimum were in P3. This study revealed that the levels of mineral elements in different varieties of green tea vary from the permissible level but the monitoring of their levels in tea plant is obligatory for future risk measurements.

Seasonal variations in the phenolic profile, antioxidant activity, and mineral content of south Indian black tea (Camellia sinensis (L.) O. Kuntze)

“…Total N was calculated using the Kjeldahl method 11 and the distillation was done using Gerhardt equipment. Wet digestion of dried and ground samples in a 9:4 mixture of nitric acid and perchloric acid resulted in the determination of macro (P, K, Mg, Ca, and Na) and micro elements (Cu, Fe, Mn, and Zn) 12 . Using a GBC model UV–Visible Spectrophotometer, P was determined spectrophotometrically in the diluted digests using the ammonium molybdate method following its interaction with ascorbic acid 12 .…”

“…Wet digestion of dried and ground samples in a 9:4 mixture of nitric acid and perchloric acid resulted in the determination of macro (P, K, Mg, Ca, and Na) and micro elements (Cu, Fe, Mn, and Zn) 12 . Using a GBC model UV–Visible Spectrophotometer, P was determined spectrophotometrically in the diluted digests using the ammonium molybdate method following its interaction with ascorbic acid 12 . By using a flame photometer (Sherwood 410) to measure potassium and sodium in digested samples, and an atomic absorption spectrophotometer to estimate magnesium, calcium, iron, copper, manganese, and zinc.…”