X-ray micro–computed tomography analysis of underutilized grains: 3D structural features

X-ray microcomputed tomography (μCT) enables non-destructive visualization of the internal microstructures of grains. In this study, underutilized grains with growing demand, including sorghum, millet, buckwheat, and quinoa were investigated as valuable alternatives to traditional cereals. A comprehensive 3D characterization of their internal architecture was performed to provide quantitative insights relevant to food processing and functional applications. By determining the spatial organization and relative volumes of major grain components, structural factors influencing mechanical behavior, hydration kinetics, nutrient distribution, and overall functional performance can be better understood. Image segmentation and reconstruction software were applied to CT datasets to generate 3D images from 2D cross-sectional images, enabling volumetric structural analysis. This approach facilitates the identification and quantification of internal microstructural features that are often inaccessible through conventional imaging techniques. The total grain volume, as well as the volume of major anatomical components, were quantified. Phenotypic characterization included grain shape, internal component morphology, and spatial organization. The embryo, endosperm, and outer layers were clearly distinguishable in all grains, while in quinoa, additional structures such as the perisperm, funicle, and cotyledons were also resolved. The CT-derived volumetric and spatial datasets generated in this study contribute to the limited body of quantitative 3D grain anatomy literature, which has predominantly focused on single crops or relied on schematic rather than true volumetric representations. These findings provide a valuable resource for advancing structural understanding and application of underutilized grains in the food sector.