Determination of alcohol concentration in distilled spirit based on PLS-FT-NIRS

In order to measuring alcohol concentration in distilled spirit accurately and quickly, a calibration model was established based on Fourier Transform Near Infrared Spectroscopy with partial least square(PLS-FT-NIRS) by Cross-Validation after the spectra were analyzed and discussed. According to the selected spectra ranges of 9747.1～7498.3 cm^-1 and 6102～5446.3 cm^-1 and vector normalization processing method, the correlation coefficient(R²) of the model, the root mean square error of cross validation(RMSECV) and the rank are 99.99%, 0.165% and four, respectively. Then the model was tested and evaluated and the result showed the R² of the test set and the root mean square error of prediction(RMSEP) are 99.80%, 0.264% respectively. The method has been applied to quick determination of alcohol concentration with satisfactory results in the distilled spirit industry.