Abstract:Two-dimensional correlation NIR spectroscopy was combined with discriminant analysis (DA) method for the identification of aged vinegar samples of different vinegar ages. A total of 100 aged vinegar samples of five different vinegar ages were selected, and the 1D NIR spectra of all samples were collected at room temperature. The two-dimensional correlation synchronous spectra and asynchronous spectra of each sample in the wavelength range of 1 001-1 830 nm were constructed with the age of vinegar as the external disturbance factor, and the spectral characteristics of the two-dimensional correlation spectra of the samples were analyzed. Based on the diagonal data (autocorrelation spectrum) of the two-dimensional correlation synchronous spectra, a discriminant analysis model was established for the old aged vinegar samples with different vinegar ages, and the identification accuracy of the model calibration set was 97.3% and that of the prediction set was 96%. The results showed that the proposed method could provide more spectral feature information with vinegar age, and provide a classification model with higher accuracy for the rapid identification of aged vinegar.