The cultivation of fresh market tomatoes has been modernized with the introduction of packing lines for cleaning, sorting and classifying. Despite of those technological changes, post harvest losses are still high, mainly due to the incidence of the mechanical damages that occurr in the transfer points and during packing. The main goal of this research was to evaluate tomato quality of cv. Debora, subject to dropping after being subjected to the cleaning step on a prototype developed in laboratory to simulate a commercial system, relating quality changes to impact magnitude (G, m/s2). Therefore, fruits were subject to a 100 rpm rotation and submitted to a fall from three different heights (10, 20 e 30 cm) and three different surfaces (foam, plastic box and metallic sheet). The impact magnitude (G, m/s2) was measured using an instrumented sphere, 70 mm Techmark, Inc., Lansing, EUA). Fruit quality after impact was evaluated by weight loss (%), internal bruising, and chemical analyses. The use of an instrumented sphere showed that a foam surface decreases maximum acceleration (G, m/s2) by about 70% for 10 and 20 cm high drops and 47% for 30 cm drop, compared to a metallic surface. Tomatoes submitted to drops from 30 cm high over metal surface showed increase on 31% on internal bruising when compared to fruits submitted to drops at the same height on the covered surface (foam). The highest weight loss (3,46%) was found in fruits submitted to a drop from 30 cm on plastic boxes. No statistical differences were observed between the different treatments. Based on the results, it could be concluded that the use of protective surfaces significantly decrease internal bruising and weight loss and tomatoes submitted to drops in plastic boxes showed a significant increase in physical damage, therefore, changes have to be made at the packaging stage.
Lycopersicon esculentum; packing line; mechanical damages
