Arracacha roots are very fragile and susceptible to mechanical damage. The postharvest handling system may cause many lesions, mainly by impacts and drops. The effect of drop impact on arracacha roots was simulated in two drop heights (45 and 90 cm) and three release positions of the roots (horizontal, vertical distal and vertical proximal). The experiment was carried out in a randomized block design, with three replicates (40 roots per and three release positions of the roots (horizontal, vertical distal and vertical proximal). The experiment was carried out in a randomized block design, with three replicates (40 roots per parcel). After the drop, roots were examined individually and the resulting mechanical damage was categorized in four types of lesions (broken, fracture, rupture and abrasion) compared to those apparently undamaged. Drop height affected directly the incidence of more serious mechanical damage, such as broken roots and ruptures. The root position also affected the resulting mechanical damage: roots released from the proximal position at 90cm drop height had significantly higher fractures incidence (40.7%), ruptures (19.2%) and superficial lesions (22.3%) than other treatments. At the 90 cm drop height, roots released from the proximal position had 40.7% of fractures, 19.2% of ruptures and 22.3% of superficial lesions; roots released from the distal position caused 45.8% of ruptures and 23.3% of broken roots. The respiration rates and deterioration of arracacha roots submitted to mechanical damage (90 cm height fall impact) and storage (5ºC and 24ºC) during four days showed that at the same temperature, mechanically damaged roots had higher respiration rates when compared to sound roots, ranging from 15.3 ml CO2 kg-1 h-1 (unbruised) to 34.4 ml CO2 kg-1 h-1 (damaged) at 24ºC. Injured roots kept at 24ºC had 84% of deterioration after four days, while those kept at 5ºC were completely sound.
Arracacia xanthorrhiza; mechanical damage; lesions; respiration; deterioration
