Investigations were carried out on: potato tubers of 4 clones of cultivar Irga, transformed with viral genome sequences in order to improve their resistance to a necrotic strain of potato virus Y (PVY^N); tubers of parent cultivar; two selected commercial cultivars. Tissue texture (expressed by puncture force and energy) and microstructure were observed after blanching and frying potato strips. A statistical analysis of the variability of texture of raw and heat-treated potatoes enabled classifying Irga and its genetically-modified clones as similar, and did not allow distinguishing a clone of special usability for frying. No differences were revealed either in the texture of the parent cultivar Irga or its genetically-modified clones during 6-month storage. Depending on the type of the thermal treatment of potato tubers, typical deformation of parenchyma tissue resulted. Similar micro-structural changes of the parenchyma tissue were observed after the thermal treatment in both the stem-end zone and the middle part of fried strips.