Abstract:To investigate the effects of xanthan gum with different molecular structure on the quality of frozen dough and baking characteristics of bread,three kinds of xanthan gum with different molecular structure were added to flour to make dough,and bread was baked after frozen storage.The fermentation rate,rheological properties,thermal stability of dough and the specific volume,hardness elasticity of bread were determined.The results showed that with the extension of frozen storage time,dough quality and bread baking properties were affected,and the addition of xanthan gum significantly reduced the degree of dough deterioration and improved bread quality. The addition of xanthan gum increased the viscoelasticity of the dough,and inhibited the starch gelatinization. The rheological results indicated that,the textural results revealed that xanthan gum enhanced the elasticity and decreased the hardness of the bread（P<0.05）.Additionally,xanthan gum increased the specific volume of frozen dough bread（P<0.05）.Xanthan gum with low molecular weight was more effective in improving the quality of bread. In conclusion,adding xanthan gum to frozen dough could enhance the quality of frozen dough bread,and xanthan gum with low molecular weight（1 400 kDa）could improve the baking characteristics of the bread,and also reduce the hydration time during the actual industrial application.