Exploring the effects of phosphorylated long-chain inulin with varying degrees of substitution on the physicochemical properties and structure of unfermented wheat dough.

This study explored the effects of phosphorylated long-chain inulin (PFXL) with varying degrees of substitution on the physicochemical properties and structure of unfermented wheat dough. Phosphorylated derivatives with substitution degrees 0.010 (PFXL-1), 0.022 (PFXL-2), 0.038 (PFXL-3), and 0.067 (PFXL-4) were prepared. PFXL groups enhanced rheological properties, tightly bound water, and water-holding capacity. The addition of PFXL changed protein particle size and zeta potential. As the phosphorylation degree rose, protein particle size shrank while electronegativity grew, enhancing system stability. Compared to the control group, the PFXL-2 group increased the relative content of tightly bound water (A) and springiness of dough by 77.10 % and 19.88 %. Concurrently, it elevated the β-sheets content of gluten proteins by 3.91 % while reducing particle size and surface hydrophobicity of gluten proteins by 47.57 % and 7.76 %. Confocal laser scanning microscopy (CLSM) revealed that PFXL-2 group formed a continuous lamellar pore structure, strengthening the gluten network. However, PFXL-4 group had adverse effects, leading to a decrease in the β-sheets content and an increase in fluorescence intensity of gluten proteins. This study showed PFXL improved unfermented dough quality at suitable substitution degrees, highlighting its potential as a functional modifier.