Insufficient gluten in dough, excessive proofing, improper surface treatment before baking (such as excessive brushing of egg liquid in soft package, too high or too low temperature of egg liquid, too early or too late operation opportunity of hard package surface, incorrect bread decoration method, too slow action, etc.). ), when the baking tray enters the oven, there is impact or strong vibration, the baking temperature is low, the baking time is insufficient, and there is no correct heat dissipation or dish dropping action after being discharged. In short, it may be any one or more of the above.

Bread making is very simple, and it is difficult to be perfect. Every link and detail needs to be well controlled. As long as there is a little problem in one place, the result will be very troublesome.