A Preliminary Study on the Physicochemical and Bioactive Characterization of Anatomical Structures of Raw and Nixtamalized Native Maize Landraces

This study presents a preliminary characterization of the physicochemical and bioactive properties of kernel structures and associated nejayote from five maize landraces in raw and nixtamalized forms. Direct and indirect hardness were determined using the flotation index and a texture analyzer. Antioxidant activity (AA), total phenolic content (TPC), and total flavonoid content were determined using DPPH and colorimetric methods. Very hard maize landraces were characterized by a mean floury‐to‐vitreous endosperm ratio of 30:70. Hard and very hard raw corn showed a similar hardness trend after nixtamalization. The tip cap exhibited among the highest levels of bioactive compounds (131.88 mgGAE/g db ). Blue and red pigmented landraces showed the highest levels of AA (27.15 mgAAE/g db) and TPC (191.33 mgGAE/g db ). Under the experimental conditions evaluated, nixtamalization was associated with increases of up to 112% in AA and 94% of phenolic content, whereas flavonoid content decreased by up to 76%. This work provides a comparative physicochemical and bioactive characterization of native maize anatomical structures under controlled nixtamalization conditions. Due to the limited number of independent experiments and restricted biological replication at the processing level, the findings should be interpreted as exploratory and indicative rather than conclusive.