The changes in the sprout compositions and starch properties of Chinese yam (Dioscorea opposita Thunb.) during germination.

Chinese yam (Dioscorea opposita Thunb.) tubers are renowned for their nutritional and medicinal properties. However, the effects of germination on their sprout composition and starch properties remain poorly understood. This study investigated the biochemical changes of Chinese yam sprouts, and analyzed the structure, physicochemical properties and digestibility of Chinese yam starch during controlled germination. Germination significantly enriched the nutritional profile of Chinese yam sprouts, with notable increases in amino acids, phenolic compounds, particularly at 16 and 24 d of germination. Germinated starch samples had lower A and B1 chains, storage modulus, short-range order, and higher B3 chains, amylose content, relative crystallinity and resistant starch level than the ungerminated sample. Besides, the XRD peaks (15°, 17°, 18°, 22°) of the germinated starch conformed to the polycrystalline diffraction pattern of A-type starch. Germination enhanced the functional composition of the sprouts and the anti-digestibility of starch. The findings demonstrated that germination enhanced the health-promoting properties of sprouts, offering a promising strategy to develop functional ingredients for functional foods.