Relative density measurement method for essence and flavor for tobacco

The invention discloses a relative density measurement method for essence and flavor for tobacco. According to the method, an infrared spectrogram of the essence and flavor for tobacco and relative density of the essence and flavor for tobacco are acquired so as to obtain a spectral matrix and a numerical matrix of an essence and flavor sample; a relative density model for the essence and flavor for tobacco is established based on partial least squares; a spectral matrix component and a numerical matrix component that meet maximum variance of the spectral matrix and the numerical matrix are acquired through the partial least squares; a corresponding mathematical model of the relative density and the near infrared spectrogram of the essence and flavor for tobacco is established according toall acquired spectral matrix components and numerical matrix components. Relative density of essence and flavor needing to measure in relative density can be acquired by only obtaining a mathematicalmodel of infrared spectru