Post-harvest nutraceutical behaviour during ripening and senescence of 8 highly perishable fruit species from the Northern Brazilian Amazon region

The post-harvest nutraceutical characteristics of highly perishable native fruits species from the Northern Brazilian Amazon region were studied during 12 day at 15 ± 1 °C and 95 ± 3% RH. Uxi and caja fruit showed climacteric behaviour while caju, açai de terra firme, camu-camu, inajá, murici and araçá-boi were non-climacteric. Soluble solids and sugars increased for climacteric fruit while total acidity remained constant for all fruits. In general, all fruit species had high levels of total phenolics (121-9889 mg GAE 100 g−1 dry weight pulp), vitamin C (31-1532 mg AA 100 mL−1 juice) and antioxidant activity (AOX) (75-2881 μmol Trolox Eq 100 g−1 dry weight, ORAC value), however, camu-camu, acai and murici were among the highest. All fruits showed an increase in phenolic content (15-82%), a simultaneous decrease in ascorbic acid in both peel (88-98%) and pulp (89-97%), while AOX increased or decreased depending on the fruit species, very likely due to the specific phenolic profile being synthesized. We propose a hypothetical model where ripening/senescence induced a redox homeostasis imbalance which in turn triggered the responses.