Impact characteristics of pears

The effect of impact on two pear cultivars have been studied in terms of maximum force, impact time, maximum deformation, permanent deformation, restitution coefficient and maximum stress. The above mentioned characteristics were related to bruise sizes and the bruise initiation was determined for a given weight and firmness. Bruise initiation was described by the restitution coefficient. The stabilization of mean values of maximum stress at different drop heights confirmed that the pear damage occurred after specified stress values were exceeded. The rate of bruise development was dependent on the fruit firmness. Firmer pears were more resistant to impact and the bruise initiation occurred at a higher impact velocity.