Bioaccessibility and antioxidant activity of phenolic compounds in frozen pulps of Brazilian exotic fruits exposed to simulated gastrointestinal conditions

Abstract

This study characterized the phenolic profile in siriguela, umbu-cajá and mangaba, as well in their frozen pulps (FPs). The bioaccessibility of phenolic compounds and the antioxidant activity of the FP dialysates were determined following exposure to simulated gastrointestinal conditions. The profile of phenolic compounds identified in fruit and FPs were relatively similar. After pulp processing, increases of 33.60% and 68.72% in free phenolics were observed for mangaba and umbu-cajá, respectively, whereas in siriguela, the free phenolic was reduced by 56.55%. Generally, phenolic levels decreased after exposure to simulated gastric conditions in all FPs. The bioaccessibility of phenolics varied among the evaluated FPs. The highest bioaccessibility was observed for gallic acid in the umbu-cajá FP (73.92%) and the lowest for gentisic acid in the mangaba FP (8.71%). Siriguela and umbu-cajá FP dialysates presented the highest capacity for the capture of the radical 2,2′-diphenyl-2-picrylhydrazyl hydrate, whereas the mangaba FP dialysate demonstrated the highest iron reducing capacity.