Reliability of vibration measurements and impact response characteristics for the quality assessment of tomatoes

Abstract

The applicability of the acoustic impulse-response and the impact response devices for t he measurement of fresh table tomato firmness states with both instruments. A high positive correlation wasfound between the maximal acceleration, measured with the impact response device, and the stiffness measured with the acoustic tester. For the impact tester, the ratio between the maximal acceleration and the impact duration was the most segregating parameter when classifying tomatoes into different firmness classes. For the acoustic tester, the repeatability of the measurements was significantly higher at the equator than at the bottom of the tomato. This was not the case for the impact tester, which gave similar results at both positions. The overall discrimant power of both methods was found to be very similar. For the acoustic tester, discrimination between different firmness states was much better when measuring at the bottom. For the impact tester, it makes not too much difference in discriminat power where to measure.