Abstract: This paper quantitatively determines the total water-soluble sugars in white tea rapidly by using Near-infrared Spectroscopy (NIRS) method.113 white tea samples,manufactured by distinct providers in different years,and of different quality grades,are used to do the determination experiments.The near-infrared spectra of these samples is acquired and analyzed in the first place.And then a quantitative analysis model of total water-soluble sugars in white tea is established by adopting partial least square (PLS) method.The experimental results show that the correlation coefficient (R) of the proposed quantitative analysis model is 0.963 9,while the root mean square error of calibration (RMSEC),the root mean square error of predication (RMSEP),and the average relative error of the validation set are 0.363,0.349 and 3.11%,respectively.The model is of good predication performance,and thus can quantitatively determinate the total water-soluble sugars in white tea accurately,rapidly and losslessly.The result indicates the feasibility of NIRS in rapid determination of total water-soluble sugars in white tea.

Key words: white tea, total water-soluble sugars, rapid determination, NIRS