Some indices of food texture were not enough to reproduce the kinetic energy. Therefore, we developed a device and an index (Energy Texture Index, ETI) that enables one to measure the kinetic energy of vibration by the food fracture using a probe mass obtained by a free running. It enabled one to define another index (Food Friction Index, FFI) that was also proposed to measure a friction of probe against a food sample. The ETI and FFI were measured for apple, persimmon, and banana as examples. The ETI and FFI showed a characteristic difference between the three fruit samples. The FFI was found to be constant even if the insertion velocity into sample is changed. The ETI and FFI have possibilities to show a new facet of food texture. (C) 2017 Elsevier Ltd. All rights reserved.