Chlorophyll and carotenoid analysis of tea by high- performance liquid chromatography and its application for quality control

The. separation and identification of pigments, chlorophylls and carotenoids, of several teas by high-performance liquid chromatography (HPLC) were described. HPLC was carried out using a Symmetry Cs column with a photodiode array detection. Pigments were eluted with a binary gradient of aqueous pyridine solution at a flow rate of 1.0 ml per min at 25°C. HPLC analyses archived the separation of more than 100 peaks of the pigments and about 78 pigment species (42 chlorophylls and 36 carotenoids) of them were identified. The presence of allomer and epimer of chlorophylls was common feature in processed teas. Pyropheophorbide was not detected in tea extracts. Pheophorbidase which involves in the formation of pyropheophorbide, could not found in intact tea leaves. Pheophorbide a, a degradation product of chlorophyll, was also detected in the most of the samples, indicating that this may be used for the indicator of quality of tea in tenns of chlorophyll. The relationship between extraction temperature ofwater and pigment concentrations are also described.