Abstract: In the present study, the effect of xylanase from S. rochei L10904 on the specific volume, extension rate, hardness and anti-aging function of steamed bread were investigated. The results showed that the optimal addition level of xylanase was 1.5 mg/kg. In such case, the minimum hardness of steamed bread was achieved; the specific volume of steamed bread increased by 0.21 mL/g compared to the control without the addition of xylanase, and the extension rate reached up to 1.69. During the first 24 h of storage, the hardness of steamed bread increased while the cohesiveness decreased rapidly. After 24 h, the hardness and cohesiveness of steamed bread changed slowly. The adherence and chewiness of steamed bread increased rapidly during the first 10 h of storage and then remained a constant level. The addition of 1.5 mg/kg xylanase could result in a relative low level of hardness, cohesiveness, adherence, and chewiness and therefore had obvious aging-delaying effect on steamed bread.

Key words: xylanase, steamed bread, aging-delaying effect