Research on internal defects of potato tubers using the nuclear magnetic resonance method

The results of experimental studies are presented, determining the internal defects of potato tubers using nuclear magnetic resonance (NMR) method, which provide access to information about the state and distribution of water at the cellular and tissue levels. In order to carry out internal defect detection studies, three groups of potato tubers were prepared, comprising conditioned and unconditioned samples. The total sampling of potato tubers amounted to 38 samples. To create hidden defects in the form of darkening of tuber pulp, the method of controlled impact on a hard surface was used. Methodology for conducting experimental studies and time parameters of NMR are described. The studied potato tubers were placed in a strong magnetic field with intensity of 1.5 Tesla. Analysis of T2 images was chosen as the main method for analyzing the obtained results, since this method allows to trace one of the most important indicators of detecting internal damage of potato tubers – lack of water in the damaged areas of the pulp. The damaged areas in the images of tubers have a dark color, while the healthy tissue is light. A comparative analysis of images obtained using NMR and full-scale images of tubers’ section was carried out, allowing to determine with high accuracy the coincidence of location of defects detected by non-invasive method with their actual location in the tuber.  The study showed the value of NMR for a detailed non-invasive method for determining hidden defects in potato tubers on automatic grading machines.

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