Studies concerning the response of potatoes to impact

. The paper presents the research results of the response of “Ramos” potatoes under impact loading conditions. The parameters characterizing the impact such as: maximum stress, maximum force, impact time, maximum deformation, permanent deformation and restitution coefficient were determined. The extent of the damage was also assessed on the basis of the parameters describing the particular bruise such as: bruise depth and width. The impact parameters were related to the bruise size in order to determine the damage threshold for the potatoes under impact loading conditions and to show which parameters describe the bruise beginning to manifest itself. For the tested potato cultivar with a weight of 160-190 g the initiation of the bruise was found to occur at an impact velocity of 1 m s -1 . This corresponded to a bruise threshold (drop height) of 50 mm. The restitution coefficient changed to an insignificant extent which amounted to 0.44-0.49 in the tested range of the impact velocity which proves that the energy losses during the potato impact are constant and independent of the impact velocity. The maximum stress increased with increasing impact velocity, reaching a constant value of 0.9 MPa for the highest impact velocities. The stabilization of the maximum stress indicates that the damage to the potato tissue was determined by exceeding the specified stress value.