Image Based Morphometric Evaluation of Process Induced Brown top Millet Grains

Abstract

Browntop millet (Brachiaria ramosa) is tightly encased in hard, persistent husks, making dehusking a major challenge in primary processing. In this study, grains obtained from local markets were subjected to controlled treatments: untreated whole grains (BTM‑W), directly dehulled grains (BTM‑C), and abrasive pre‑treatments of two, four, and six minutes (BTM‑A2, BTM‑A4, BTM‑A6). Dimensional characterization using digital image analysis revealed significant reductions in grain length, width, and perimeter across treatments. The untreated whole grain (BTM‑W) exhibited the maximum mean length of 3.240 ± 0.165 mm, whereas BTM‑C (2.001 ± 0.044 mm) and BTM‑A2 (1.922 ± 0.189 mm) recorded substantially lower values. Width measurements showed BTM‑W at 1.813 ± 0.051 mm, with processed variants ranging between 1.560–1.627 mm, reflecting moderate reductions. Perimeter values followed a similar trend, with BTM‑W at 7.923 ± 0.282 mm, while BTM‑C (5.700 ± 0.140 mm) and BTM‑A2 (5.663 ± 0.254 mm) showed the most pronounced decreases. Digital imaging through a stereo zoom microscope provided detailed visual evidence of these morphological transformations, confirming that pre‑treatment disrupts husk adhesion and modifies pericarp integrity, thereby facilitating husk removal. The findings demonstrate that abrasive pre‑treatment induces measurable changes in grain morphology, supporting the development of standardized protocols for Browntop millet processing. Image‑assisted morphometric analysis proved to be a robust, non‑invasive, and economical approach for evaluating grain quality parameters, strengthening the scientific basis for millet‑specific processing innovations and contributing to dietary diversification and food security.