Xanthan gum can improve the freeze-thaw stability of frozen foods. However, the high viscosity and long hydration time of xanthan gum limits its application. In this study, ultrasound was employed to reduce the viscosity of xanthan gum, and the effect of ultrasound on its physicochemical, structural, and rheological properties was investigated using High-performance size-exclusion chromatography (HPSEC), ion chromatograph, methylation analysis, ¹H NMR, rheometer, etc.. The application of ultrasonic-treated xanthan gum was evaluated in frozen dough bread. Results showed that the molecular weight of xanthan gum was reduced significantly by ultrasonication (from 3.0 × 10⁷ Da to 1.4 × 10⁶ Da), and the monosaccharide compositions and linkage patterns of sugar residues were altered. Results revealed that ultrasonication treatment mainly broke the molecular backbone at a lower intensity, then mainly broke the side chains with increasing intensity, which significantly reduced the apparent viscosity and viscoelastic properties of xanthan gum. The results of specific volume and hardness showed that the bread containing low molecular weight xanthan gum was of better quality. Overall, this work offers a theoretical foundation for broadening the application of xanthan gum and improving its performance in frozen dough.

黄原胶可以提高冷冻食品的冻融稳定性。但黄原胶粘度高、水化时间长限制了其应用。^{在本研究中，采用超声波降低黄原胶的粘度，并使用高效尺寸排阻色谱 (HPSEC)、离子色谱、甲基化分析、 1}研究了超声波对其物理化学、结构和流变性质的影响。核磁共振氢谱、流变仪等。评价超声处理黄原胶在冷冻面团面包中的应用。结果表明，超声处理后黄原胶的分子量显着降低（从3.0×10 7 ^Da 降至1.4×10 ⁶  Da），并且单糖组成和糖残基的连接模式发生改变。结果表明，超声处理在较低强度下主要破坏分子主链，随着强度的增加主要破坏侧链，显着降低黄原胶的表观粘度和粘弹性。比容和硬度结果表明，添加低分子量黄原胶的面包品质较好。总的来说，这项工作为扩大黄原胶的应用和提高其在冷冻面团中的性能提供了理论基础。