Muhammad Usman Amjad, Saman Azeem, Lijuan Wang, Baocheng Xu, Yue Tian, Xinjing Dou
In this study, native inulin was phosphorylated and used as a stabilizer in duck-fat-based whipped cream to investigate its effects on emulsion stability, rheological properties, whipping performance, and sensory quality. Characterization of phosphorylated inulin showed a phosphorus content of 0.38% and a degree of substitution (DS) of 0.020. FTIR analysis revealed phosphate-associated absorption bands at approximately 1220 and 992 cm-1, attributed to P = O and P-O-C stretching vibrations, respectively, supporting the successful phosphorylation of inulin. Within the PI series, the average particle size decreased as the phosphorylated-inulin addition level increased, reaching 629 ± 5 nm in PI-12, consistent with the CLSM observations. The absolute magnitude of the negative zeta potential generally increased with the phosphorylated-inulin addition level. All emulsions exhibited shear-thinning behavior, with storage modulus (G') exceeding loss modulus (G″). Higher phosphorylated-inulin addition levels were associated with longer whipping times and lower overrun. No measurable serum loss was detected for PI-6, PI-9, or PI-12. Air bubbles appeared smaller and more uniformly distributed at higher phosphorylated-inulin addition levels. The preliminary sensory assessment showed higher mean texture and smoothness scores for formulations containing 12 g/batch. Within the phosphorylated-inulin series, PI-6 (6 g/batch) was the lowest tested addition level at which no measurable serum loss was detected after 3 h at 22 °C, although higher addition levels further increased viscosity and viscoelastic moduli. Increasing the phosphorylated-inulin addition level above PI-6 further prolonged whipping time and reduced overrun. Further studies should evaluate storage stability and oxidative stability to validate long-term performance.