COMPRESSION DAMAGE AS THE PRINCIPAL FACTOR IN MECHANICAL INJURY OF PINEAPPLE POSTHARVEST

The pineapple, besides presenting numerous sensorial qualities, shows high dietary value. The purpose of this work was to evaluate some physicochemical changes of ‘Pérola’ pineapple subjected to different types of mechanical injuries, simulating the main damages suffered for this fruit from harvest to marketing. Fruit were subjected to the following treatments: T1: non-injured fruit (control); T2: one 60 cm free fall; T3: four longitudinal cuts (70 mm long and 2 mm deep); T4: eight perforations (3×2 mm) in the fruit base; and T5: compression for 30 min (equivalent force of 160 Newton). After treatments, the fruit were stored for 15 days at 11°C and 85% RH. Every five days, the fruits were evaluated for firmness (N), pulp translucency (in scale from 0 to 4, where 0 = opaque, 4 = 100% of translucent pulp), juice percentage (%), ratio of soluble solids/titratable acidity, ascorbic acid (mg ascorbic acid 100 g^-1) and pulp color (L*, a* and b*). The compression treatment showed a significant loss of firmness during storage, reaching 48% after 15 days. The translucency was not significantly different between the treatments. The juice percentage that was initially 51.8% decreased to a level between 41 and 45% after 15 days of storage. The ratio of soluble solids/titratable acidity that initially was 26.35 decreased to around 18. The ascorbic acid increased in all treatments along the storage. The values of L*, a* and b* were not significantly different between treatments. It was considered the compression was the more important factor in mechanical injury of ‘Perola’ pineapple at postharvest, which usually happens during transportation.