Increase in physicochemical, amylase-amylopectin, and β-carotene in phosphorylated starch of Banggai Yam (Dioscorea alata L.)?

Limited knowledge exists regarding the effects of chemical modification on the relationship between structure and bioactivity in non-conventional starches, restricting their application as bioactive carriers. This study examines the impact of sodium tripolyphosphate (STPP) phosphorylation on the physicochemical properties and β-carotene retention of Banggai yam starch. Starch samples were treated with 2–10% STPP under alkaline conditions and subsequently analyzed for basic composition, amylose–amylopectin content, and β-carotene levels. Phosphorylation resulted in increased carbohydrate content and reduced protein levels, while apparent amylose content rose markedly (from approximately 45% to 57%), indicating structural alterations. β-carotene retention also improved (from about 0.031% to 0.037%), with no further increase observed at higher STPP concentrations, suggesting that initial modification suffices to stabilize the bioactive compound. These results demonstrate a direct association between phosphorylation-induced structural changes and enhanced retention, highlighting the potential of modified starch as a carrier for bioactive compounds. The study provides new insights into the interplay among structure, function, and bioactivity in phosphorylated starch, supporting its application in the development of functional foods.