Physicochemical characterization and antioxidant capacity of popcorn nejayote

Abstract

The pursuit of reusing agribusiness residues towards decreasing their environmental impact has led to the study of its components to know their possible applications. The nejayote is the alkaline wastewater of different food products of nixtamalized corn. This study characterized the physicochemical properties of popcorn nejayote (NP) and determined its total phenolics content (TP) and antioxidant capacity by standard synthetic assays (ABTS and DPPH) and physiologically relevant ones (reducing power -RP-, hydroxyl radical scavenging activity -OH-, and iron chelation IRON). NP antioxidant capacity determined by ABTS, and DPPH methods were 387.9±0.7 and 419.3±2.9 mM Trolox equivalents (mM TE)/mL, respectively. The NP showed 296% RP compared to a control solution of coumaric acid (0.1 M). Also, the NP was obtained at 143% IRON compared to a control solution of caffeic acid (0.1 M). In the case of OH, values ranged from 27% to 45% compared with control solutions. TP was 0.26±0.006 μg gallic acid equivalents/mL (mg GAE/mL). Pearson's correlation analysis found that TP is correlated to the OH, IRON, and DPPH, while IRON activity correlates with OH and ABTS. And finally, OH correlated with DPPH. To the best of our knowledge, this study is NP's first antioxidant capacity report.