Effects of Different Thawing Methods on Dough Characteristics and Product Quality of Frozen Smashed Bean Bun

In order to study the effects of different thawing methods on the properties and edible quality of frozen dough of smashed bean bun, five methods including cold thawing at 4℃, ultrasound-assisted thawing, constant temperature and humidity thawing, air bath shock thawing and microwave thawing were adopted, and the water migration, thermodynamics and rheological properties were studied. The moisture fluidity, texture, color and cooking quality of smashed bean bun were further analyzed. The results showed that significant differences in A21, A22, elastic modulus G', viscous modulus G" and freezable water content of raw dough of smashed bean bun among five thawing methods(P<0.05). Water distribution analysis indicated that the change of strong bonding water of raw dough thawed at 4℃ was the smallest. The dough thawed by microwave had the highest viscoelastic value based on analysis of dynamic rheology. According to the DSC analysis, the frozen water content of the dough thawed by air bath shock was the highest. Besides, there were significant differences in water distribution, texture, color and cooking characteristics of frozen dough treated by different thawing methods(P<0.05). The water fluidity showed that the content of A21 in ultrasound-assisted group was the lowest. The texture properties indicated that the hardness of the cold storage and thawing group at 4℃ were the lowest and the chewiness was the best. The most stable color quality and cooking quality were exhibited in the constant temperature and humidity thawing group. The microwave thawing group had the lowest specific volume. This study showed that, cold thawing at 4℃ could reduce the loss of water and maintain the comprehensive quality of the frozen smashed bean bun dough. Constant temperature and humidity thawing can effectively reduce the cooking loss, and shorten the thawing time compared with cold thawing at 4℃. The thawing conditions of other thawing methods in frozen smashed bean bun dough still need further study. © 2021, Editorial Department of Journal of Food Science and Technology. All right reserved.