The relationship between physical properties of tubers measured during pendulum impact tests and tuber fracture damage

Abstract

The relationship between physical factors measured electronically by using a pendulum (energy absorbed during impact, calculated from rebound of the pendulum arm, deformation, and time of contact of the indentor head with the tuber during impact) and fracture damage (external and internal damage) was investigated in potato genotypes showing a wide range of damage susceptibility. The physical factors were highly correlated one with another and all gave good correlations with fracture damage. However, the highest correlations with damage were generally found for energy absorbed and permanent deformation which, for example, respectively explained 91% and 93% of the variation in external damage. A slight improvement, particularly with tubers showing the maximum score for external damage, was found when the damage was expressed as a damage rating calculated from a multiple regression of external damage + depth of damage + width of damage.