Research to moisture content,free form amino acids,polyphenols quality ingredients of Congou black tea by near infrared spectroscopy

Objective: This paper gave a new method about detecting the moisture content,free form amino acids,polyphenols quality of Congou black tea by near infrared spectroscopy.Methods: There were 240 test samples,180 samples of them used to be a correction stage as the remaining 60 samples a prediction set. Each model is optimized,the best waves of the number of segments and best pretreatment method for modeling use to establish the quantitative prediction model by OPUS 7.0 software.The smooth points were 17 and dimension was 1.Results:The models predicted a high accuracy which can be used to predict the moisture content,free form amino acids,polyphenols quality of Congou black tea. The calibration correlation coefficients( Rc) were 92.76% ~ 99.28%,correcting root mean square errors( RMSEC) were 0.016~0.0437,predictive correlation coefficient( Rp) was 97.41%~98.46%,and the RMSEP was 0.00915~0.0168.Each model calibration set and prediction set had a higher degree of fit,the prediction performance model of free form amino acids > moisture > polyphenols. Conclusion: The combination of near- infrared spectra of each prediction model to predict the performance had an excellent organoleptic results which established for Congou black tea quality evaluation.