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.