Titration curve for the determination of free lithium in a lithium-boron alloy

A simple and available method for identification and authentication of edible vegetable oils using a smartphone and chemometric analysis is presented. Identification of oils by the region of origin and species (olive, sunflower, rapeseed, cotton, etc.), as well as their authentication (authenticity and falsification) were carried out by the intrinsic color of vegetable oils and fluorescence under irradiation of the samples with monochromatic ultraviolet light (A = 365 nm). The iPhone X and iPhone XIII smartphones (Apple, USA) equipped with a specialized software (RGBer) were used as a color-recording device in the study of optical and colorimetric characteristics. A smartphone-based test device and a method for measuring colorimetric parameters in an additive RGB system for identification and authentication of edible vegetable oils are proposed. The processing of the data array (for three variables R, G, and B) was carried out using the XLSTAT software product. To differentiate the samples by the region of origin and species, the method of principal components and hierarchical cluster analysis were used. Approbation of the developed approach was carried out on the samples of commercially produced vegetable oils purchased in retail stores. The use of algorithms of chemometric analysis made it possible to establish the authenticity of vegetable oils, identify them by the region of origin, and to reveal facts of falsification by diluting expensive oils with cheaper ones. The developed method for assessing the quality of plant products is advantageous for the simplicity of hardware design, the availability of technical means and materials used, the possibility of in situ analysis without involving highly qualified specialists, and the clarity and speed of obtaining information.

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