小麦粉面团形成过程水分状态及其比例变化

为研究醒面对冷冻面团品质的影响，本文研究了醒面过程中（0、30、60、90、120 min），面团水分分布的变化规律以及面团冷冻后冰晶分布、微观结构和蠕变恢复特性的变化。结果表明：随着醒面时间的延长，面团中可冻结水含量降低了0.96%；微观结构的结果表明，面团在冻结过程中形成的冰晶空隙和数量逐渐减小，冰晶分布越来越均匀；随着醒面时间从0 min延长至120 min，冷冻面团的平均空隙面积从22.65减小到11.80，空隙数目从10627.00减少到3346.00；随着醒面时间的延长，在蠕变阶段，冷冻面团的最大蠕变柔量J_max显著增加（P<0.05），零剪切粘度η₀显著降低（P<0.05）；面团醒发120 min后，冷冻面团最大蠕变柔量J_max降低了0.50×10⁻⁴ Pa⁻¹，零剪切粘度η₀降低了0.43×10⁵ Pa⁻¹，这说明冷冻面团的硬度降低，面团的形状更容易保持；在恢复阶段，瞬时柔量J₀与黏弹性柔量J_m分别增加了1.26×10⁻⁴和2.88×10⁻⁴ Pa⁻¹，冷冻面团的恢复力增加。综上，醒面降低了面团中可冻结水的含量，提高了面团的持水力，减小了冷冻过程中冰晶对面团网络结构的破坏，从而提高了冷冻面团的品质。

Changes of water status and proportion during wheat flour mixing

To study the effect of resting on the quality of frozen dough, the changes in the moisture state of the dough during the resting process (0, 30, 60, 90, 120 min), the moisture distribution of dough and their effects on ice crystal distribution, microstructure, and creep recovery characteristics after dough freezing were investigated. The results showed that the freezable water content in the dough was decreased by 0.96% with the extension of the resting time. The pores and number of ice crystals formed in the dough during the freezing process gradually decreased and the distribution of ice crystals became more and more uniform. The average pore area decreased from 22.65 to 11.80 with the extension of the resting time from 0 min to 120 min, and the number of pores decreased from 22.65 to 11.80 with the extension of the resting time. The maximum creep flexibility J_max increased significantly (P<0.05) and the zero shear viscosity η₀ decreased significantly (P<0.05) during the creep phase as the resting time was extended. After resting for 120 mins, the maximum creep flexibility J_max of frozen dough decreased by 0.50×10⁻⁴ Pa⁻¹, and the zero shear viscosity η₀ decreased by 0.43×10⁵ Pa⁻¹. This indicated that the hardness of frozen dough decreases and the shape of the dough was easier to maintain. During the recovery process, the instantaneous flexibility J₀ and viscoelastic flexibility J_m increased by 1.26×10⁻⁴ and 2.88×10⁻⁴ Pa⁻¹, respectively, and the recovery force of the frozen dough increased. In summary, resting process of dough would reduce the content of freezeable water, improve the water holding capacity, and reduce the damage of ice crystals to the dough network structure in the freezing process to improve the quality of the frozen dough.