Studies on Non-destructive Evaluation Firmness of Pear (Part 1)

Firmness Determination by an Impulse Striking

Abstract

We developed a device to evaluate by non-destruction firmness of pear (La-France). The device calculates the spring constant of the pear from its mass and the natural frequency number when vibrated lightly. The device is equipped with two kinds of hammers, and it is assumed that the device selects it by mass of a pear automatically. There is a certain characteristic in which the spring constant is different according to the firmness of the flesh of the pear. Finally, the pear can be judged if it is just right for eating, by comparing the measured data with the approximate type, which is already calculated.