The invention relates to a method for detecting
urea-doped milk based on synchronous-asynchronous two-dimensional near-
infrared related spectra. The method comprises the following steps: 1, preparing pure milk for experiments and
urea-doped milk; 2, respectively scanning the near-
infrared spectra of the pure milk for experiments and the
urea-doped milk; 3, calculating to obtain the normalization synchronous-asynchronous two-dimensional near-
infrared related spectrum matrix of the pure milk for experiments and the normalization synchronous-asynchronous two-dimensional near-infrared related spectrum matrix of the urea-doped milk; 4, building a discrimination model with a
categorical variable matrix by a multi-dimensional partial
least squares; 5, scanning and calculating unknown sample milk to obtain the synchronous-asynchronous two-dimensional near-infrared related spectrum matrix of the unknown sample milk, and substituting into the discrimination model to obtain whether urea is doped or not. Similarity and difference information of a to-be-analyzed
system, changing with external interference, are fully utilized, and the influence of the single adoption of synchronous spectrum or asynchronous spectrum matrix redundant information on the model is overcome. The method is simple and scientific, and the analysis efficiency and the discriminating accuracy are high.