ESTIMATION OF SOME POSTHARVEST LOSSES IN TOMATO DURING SIMULATED TRANSPORT OPERATION

This study was conducted to estimate the extent of the damage occurred in tomato crop during transportation. A simulation prototype for transport process was designed and five levels of vibration frequency (5, 7.5, 10, 12.5 and 15 Hz), three vibration durations (30, 60, 90 min) and three box positions (top, middle and bottom) were used to estimate the mechanical damage occurred in tomato fruits. The damage was evaluated based on three different parameters (damage ratio, the equivalent bruise index EBI and bruise area index BAI). Also, the effect of the studied variables was investigated on weight loss and firmness. The results revealed that damage ratio, EBI, BAI and weight losses increased and firmness values decreased by increasing vibration duration especially in the upper boxes for all vibration frequency levels. The results showed that the highest values of damage ratio, EBI, BAI and weight losses and the lowest value of firmness were recorded at the upper box when the simulation system was operated at vibration frequency of 7.5 Hz for a duration of 90 min compared to the other frequency levels. The information obtained from this study is very important when designing handling equipment, suspension systems, conveyor belts and packaging methods to reduce mechanical damages of fruits and vegetables.