A Comprehensive Review of Starches From Diverse Millets: Composition, Structure, Functionality, and Strategies for Genetic Improvement.
Abstract
Millets are a diverse group of underutilized C4 cereals with high photosynthetic efficiency and resilience to marginal environments; however, the functional and nutritional potential of their starches remains largely untapped. This review provided a systematic summary of current research in millet starches, covering extraction methods, multiscale structural features, physicochemical properties, modification strategies, and the genetic basis of starch biosynthesis. The main findings revealed that millet starches exhibited pronounced inter‑ and intraspecies diversity in structure and physicochemical properties, with amylose content ranging from 0.9% to 39% and relative crystallinity from 14.5% to 69%, thereby offering a broad spectrum of textural and nutritional functions. Chemical, physical, and enzymatic modifications each offered distinct advantages for tailoring starch structure, pasting behavior, thermal stability, and digestibility, and combined approaches enabled synergistic functional enhancement. Meanwhile, genetic and breeding strategies provided complementary routes for structural and functional improvement. Despite progress, significant gaps persisted regarding the specific genes, allelic variants, and regulatory networks controlling starch biosynthesis and functional diversity in millets. Future efforts should integrate standardized analytical methodologies, predictive structure-function modeling, green modification technologies, and genome‑editing platforms to unlock the full potential of millet starches as versatile, eco‑friendly, and health‑promoting ingredients.