Changes in bioaccessibility, polyphenol profile and antioxidant potential of flours obtained from persimmon fruit (Diospyros kaki) co-products during in vitro gastrointestinal digestion

Abstract

The aim was to evaluate (i) the phenol and flavonoid recovery and bioaccessibility indexes, (ii) the stability of individual polyphenolic compounds and (iii) the antioxidant activity of persimmon flours (cultivars 'Rojo Brillante' and 'Triumph') during the in vitro digestion. The recovery index for phenolic and flavonoid content was dependent on flour type and digestion phase. After the dialysis phase, the bioaccessibility for phenolic compounds from both flours was similar; for flavonoids it was higher in 'Triumph' than 'Rojo Brillante' flour. After in vitro digestion, 13 polyphenolic compounds were detected in both flours, of which only six were detected in the intestinal phase. Their antioxidant activity (ABTS+, FRAP and DPPH) decreased after intestinal phase, while their chelating activity (FIC assay) increased in both flours. So, persimmon flours could be included in the formulation of foods to improve either their scarcity of bioactive compounds or an unbalanced nutritional composition.

Keywords: Antioxidant; Bioaccessibility; In vitro digestion; Persimmon; Polyphenol compounds.