Reasons for unsmooth appearance:

Common surface problems of steamed bread are: cracks, cracks, blisters and so on.

Cracks in steamed bread are mostly caused by low proofing humidity, which can be solved by adjusting proofing humidity.

Cracks may be caused by factors such as too low dough moisture, too high dough pH value, insufficient kneading, too much cloth and insufficient dough proofing.