PURPOSE: To obtain a donut dough always keeping a required amount of a stable quality at a needed time by thawing and fermenting a non-fermented frozen yeast bread dough respectively under specific environmental conditions.

CONSTITUTION: A non-fermented frozen yeast donut dough is first thawed and heated to the dough center temperature of ≥14°C under an environment comprising a temperature of 15-22°C and a humidity of 40-60°C. The heated dough is further heated to 35-40°C at a heating rate of ≥1°C/min under an environment comprising a humidity of 50-70°C, and subsequently fermented under an environment comprising a humidity of 50-70°C and a temperature of 35-40°C. The fermentation of the dough under the environment comprising the humidity of 50-70% and the temperature of 35-40°C is usually performed for 5-30min.