Spectroscopic and Microscopic Characterization of Millet Starch Digestibility

Given the role of millet as a staple food and its implications for digestion-related health outcomes, the investigation of millet starch digestion has garnered significant attention from the food industry. Several biophysical methods have become essential tools in contemporary scientific research, enabling comprehensive studies on starch digestion. X-ray diffraction elucidates changes in starch crystallinity and structure during digestion. Differential scanning calorimetry assesses the heat absorbed or released during starch gelatinization, offering insights into its structural changes and susceptibility to enzymatic degradation. Rheology analyses how changes in the physical properties of millets during digestion affect their flow and deformation behavior, providing information on the viscoelastic properties of starch. Scanning electron microscopy is crucial for visualizing the morphological characteristics of starch granules. Fourier transform infrared spectroscopy also revealed changes in the molecular structure of starch as it degrades, elucidating the progression of the digestion process. A comprehensive understanding of these advanced techniques will lead to improved material design, enhanced process efficiency, and breakthroughs in various scientific fields. This review aims to present an overview of prominent biophysical techniques employed as essential tools to study the structure and other properties implicated in the digestion of starches and apply them to millet starch as examples.