Tea color measurement with fiber spectrometer

Surface color of tea is an important parameter to estimate the quality of tea. A method based on a fiber spectrometer to detect the surface color of tea is introduced. The reflective spectrum of tea is detected by the spectrometer and normalized by the reflective spectrum of a white standard ceramic plate. Then the CIE tristimulus values of tea are calculated according to the corresponding theoretical expressions and used to characterize the surface color of tea. A tungsten bromine light is used as light source in the experiment. The reflective spectra of tea and white ceramic standard plate are automatically and repeatedly recorded by the spectrometer. The experimental results indicate that this method is simple, rapid, and it has the reproducibility of about 1%.