Unveiling Microstructural and Physicochemical Divergence Among High‑Altitude Teosinte Caryopses

ABSTRACT Background and Objectives This study determined the divergence of microstructural and physicochemical characteristics of caryopses among high‐altitude Zea mays subsp. mexicana, Z. mays subsp. parviglumis and Zea diploperennis , targeting anatomical proportions, thousand kernel weight, dimensions, starch granule size, contents of dietary fiber, starch, protein, and ash, as well as amino acid and mineral profiles. Findings Conserved microstructural features across taxa were observed. Significant physicochemical differences were observed among teosintes in protein (8.08–10.11 g/100 g db), ash (2.56–2.91 g/100 g db), total starch (36.95–39.29 g/100 g db), resistant starch (4.72–6.01 g/100 g db), and starch granule diameter (6.53–12.83 µm). Mexicana showed the largest starch granules and the highest ash and Fe (13.66 mg/100 g) contents. Teosintes showed high total dietary fiber (50.06–53.19 g/100 g db) and low lysine and tryptophan content. Conclusions Although microstructural features are conserved across teosinte taxa, results report significant compositional differences that could aid selection and utilization in downstream work. Significance and Novelty This is the first integrated microstructural and physicochemical comparison of these high‐altitude teosinte caryopses, explicitly reporting dietary fiber and starch fractions, as well as amino acid and mineral profiles. Thus, providing baseline data to aid subsequent breeding and food‐science research.