Abstract: A deformeter for testing the firmness of fruit as an indication of its maturity includes a support for an individual fruit effective to convey the fruit to a testing location, at which sensors are urged to contact the fruit surface lightly, preferably on a diameter, to establish a datum position. The sensors are then urged to contact the fruit with a predetermined, deforming pressure. At least one more sensor moves correspondingly into the fruit to establish an indented position. The two sensor positions are electrically noted and are subtracted to afford an indented distance from datum position indicative of firmness and so maturity. A modification uses a pair of first sensors arranged on opposite sides of the fruit in a trailing position, the pairs operating in sequence and being arranged with all sensors substantially in the same, vertically adjustable plane.