Effects of STMP/STPP Phosphorylation on the Physicochemical, Structural, and Sensory Characteristics of Banggai Yam Starch-Based Prebiotic Bread

Phosphorylated starch has emerged as a promising functional ingredient for developing low-glycemic and prebiotic bakery products, as it can modify starch digestibility, hydration behavior, and structural stability. However, the application of phosphorylated Banggai yam starch in bread systems remains poorly understood, particularly regarding the mechanistic relationship between phosphate-induced cross-linking, bread quality, and potential prebiotic functionality. This study aimed to evaluate the effects of STMP-, STPP-, and STMP/STPP-phosphorylated Banggai yam starch on the physicochemical, functional, structural, and sensory characteristics of prebiotic bread. Bread was formulated using different substitution levels of phosphorylated starch, followed by analyses of moisture content, swelling power, solubility, loaf expansion, crumb structure, and sensory properties. The results demonstrated that phosphorylation significantly enhanced moisture retention, water-holding capacity, and structural stability, while reducing loaf expansion and modifying the crumb microstructure at higher substitution levels. Moderate substitution levels produced breads with relatively uniform pore distribution, acceptable sensory properties, and improved hydration behavior. Furthermore, controlled swelling and solubility indicated reduced molecular mobility and restricted enzymatic accessibility due to phosphate-induced cross-linked starch architecture, suggesting a potential reduction in the starch hydrolysis rate and improved prebiotic functionality. These findings provide mechanistic insight into the phosphorylation-driven modulation of Banggai yam starch functionality and demonstrate its potential for developing functional bakery products with improved technological and nutritional performance.