PH—Postharvest Technology: Damage to Loquats by Vibration-simulating Intra-state Transport

Measurements of vibrations transmitted from the floor of a modern semi-trailer with air-ride suspensions were carried out during transportation of loquats (Eriobotrya japonica Lindl.) from Spain to Italy. The obtained values of the power spectral density (PSD) were used to simulate transportation vibrations by means of an electro-dynamic shaker. A column of crates containing loquats were stressed with the shaker to cause damage similar to that due to transportation. A comparative test was also carried out to evaluate the benefits of insulating sheets inserted in to the container of fruits. The PSD was dependent on the position along the floor of the semi-trailer. For the entire route, PSD showed a characteristic peak at 16 Hz and, in the range 13–46 Hz, it was higher in the rear and middle positions than in the front position. In the range 13–25 Hz, the acceleration along the column of the crates containing loquats and submitted to the random vibration-simulating transportation was greatly amplified from the bottom to the top. Nearly all the examined loquats showed deterioration due to vibro-pressure and friction stresses mainly consisting of translucent or darkened bruises and streaks. No great differences in the frequency of the damaged fruits emerged between the three positions of the crates along the column. The use of insulating sheets reduced the percentage of damaged fruits by 20–40%.