Abstract
A colorometric device is proposed to identify and establish the falsification of various types of starch and flour by diffuse reflection of UV and IR radiation from LEDs. The color characteristics of the samples (values of RGB digital channels) were determined using the cameras of OnePlus 10 Pro and iPhone 14 smartphones with PhotoMetrix PRO®, ColorGrab, RGBer applications installed. IR spectra in the near infrared range (4000–10000 cm–1) were recorded using a Fourier transform IR spectrometer. To process the array of colorometric and spectral characteristics data, specialized software packages were used: TQ Analyst 9, The Unscrambler X, XLSTAT. The identification features were the location of clusters for certain types of starch and flour in the methods of main components and hierarchical cluster analysis. The optimal wavelengths for establishing qualitative falsification of the studied samples were determined: for starch, the simultaneous participation of all LEDs (365, 390, 850 and 880 nm), for flour, the use of LEDs with irradiation wavelengths of 365 and 390 nm. The assessment of qualitative falsification was carried out using graphs of the dependence of the F1 component on the mass fraction of the added foreign additive in starch or flour. The operability of the colorometric method was confirmed by the method of infrared spectroscopy with Fourier transform in the near field