In the present study,the effect of xylanase from S.rameus L2001 on the specific volume,extension rate,hardness,moisture content and color of steamed bread was investigated.The results showed that the optimal amount of xylanase in steamed breads was 0.9 mg/kg.The prepared samples had the largest volume and the smallest hardness,and showed a 9.14% increase in specific volume,a 16.39% increase in extension rate,and a 19.0% decrease in hardness compared with the control samples.During the first 10 h of storage,the hardness,cohesiveness,adherence,and chewiness of steamed breads changed slowly,but the hardness obviously increased and the values of cohesiveness,adherence,and chewiness tended to decrease with increasing storage time.The addition of xylanase from S.rameus L2001 at 0.9 mg/kg resulted in decreases in the hardness,cohesiveness,adherence,and chewiness of steamed breads.As a consequence,the ageing of steamed breads was inhibited most obviously.