(中国农业科学院农产品加工研究所/农业农村部农产品加工综合性重点实验室 北京 100193)
(Institute of Food Science and Technology， Chinese Academy of Agriculture Sciences / Key Laboratory of Agro-Products Processing， Ministry of Agriculture and Rural Affairs， Beijing 100193)
为明确不同搅拌时间及冻藏过程中，非发酵冷冻面团中水分的状态及分布情况，采用低场核磁共振技术(LF-NMR)测定粉质仪和面过程中面团及其冻藏后的水分结合状态及比例的变化情况。结果表明:在面团搅拌过程中，刚离开500 BU时的面团中强结合水比例(A21)最高，弱结合水比例(A22)最低，水分结合状态最好，面筋充分水合。不同搅拌时间的面团冻藏后，内部出现形状不规则、分布不均匀的冰晶孔洞；然而，刚离开500 BU的面团在冻藏后A21值仍最高，内部冰晶孔洞数量较少，且冰晶孔洞面积也较小，水分结合状态较好。结论:粉质仪和面过程至刚离开500 BU的面团中水分结合状态最好，面筋网络结构充分形成，内部水分子流动性最低；冻藏后，刚离开500 BU的面团水分结合状态仍较好，内部水分子较稳定。
In order to clarify the state and distribution of water in non-fermented frozen dough at different mixing times and during freezing storage， low-field nuclear magnetic resonance (LF-NMR) was used to determine the moisture state of dough and after freezing during the dough mixing process by farinograph. The results showed that: In the dough mixing process， the proportion of strongly bound water (A21) in the dough just after leaving 500 BU was the highest and the proportion of weakly bound water(A22) was the highest. At this time， the water binding state was the best， and the gluten was fully hydrated. Ice crystal pores with irregular shapes and uneven distribution appeared inside the dough with different stirring times after freezing. However， the A21 value of the dough that had just left 500 BU was still the highest after freezing， the number of internal ice crystal pores was small， and the area of ice crystal pores was small. The moisture binding state was better. Conclusion: The moisture binding state of the dough that just left 500 BU from the farinograph kneading process was the best， the gluten network structure was fully formed， and the mobility of internal water molecules was the lowest. After frozen storage， the moisture binding state of the dough that had just left 500 BU was still good， and the internal water molecules were relatively stable.