Identification and Authentication of Cow Milk Powder Using a Smartphone and Chemometric Analysis

The possibility of identifying and authenticating cow milk powder by the method of chemical colorimetry of the fluorescence of samples using a smartphone camera and chemometric analysis is shown. A fundamental test device for direct colorimetric analysis of milk powder is proposed, excluding the stage of sample preparation. Fluorescence excitation is carried out with a portable source of monochromatic UV radiation (λ = 365 nm). The colorimetric parameters of milk powder fluorescence in RGB space are recorded using a smartphone camera. We use chemometric processing of the calculated analytical signal, which makes it possible to reduce the analysis time and visualize the studied data. The data array of the fluorescence colorimetric parameters (RGB) are evaluated by principal component analysis (PCA) and hierarchical clustering analysis (HCA) using the XLSTAT software.