Physicochemical characterization, antioxidant capacity, total phenolic and proanthocyanidin content of flours prepared from pequi (Caryocar brasilense Camb.) fruit by-products

- Flours from pequi peels (fruit production wastes) were produced and characterized.
- Polysaccharide fraction of the dietary fiber comprised of cellulose, hemicellulose and pectin.
- Main fractions were rhamnogalacturonans, arabinogalactans, β-xylans and glucomannan.
- Flours have high contents of polyphenols and non-extractable proanthocyanidins.
- Flours were shown to be potential sources of dietary fiber and natural antioxidants.

The potential of pequi by-products as substrates for the production of flours rich in antioxidant dietary fibers was evaluated. Dietary fiber contents ranged from 39.8 to 43.3 g/100 g with pectic polysaccharide fraction constituted of rhamnogalacturonans and hemicellulose fraction consisted of arabinogalactans, xylans and glucomannans. Total polyphenols, non-extractable proanthocyanidins (NEPA) and carotenoid contents of the flours were determined (respectively, 15.5-17.4 g GAE/100 g, 215.54-346.84 mg/100 g and 2116.52-3499.03 μg/100 g). The antioxidant capacities of pequi by-product flours (986.94-1154.42 μM TE/g ABTS; 44.43-48.02 g/g DPPH; and 3027.31-3216.27 μmol Fe2SO4/g FRAP) were found to be exceptionally higher than those of fruits and fruits by-products reported in the literature. Exocarp removal promoted no significant changes in the technological properties of the flour, except for color. Results showed promising prospects for future exploitation of pequi peel as a potential source of dietary fiber and natural antioxidants.