菊粉对面团中水分迁移行为的影响规律研究

为了研究不同聚合度菊粉对面团中不同流动性水分迁移行为的影响规律,以短链、天然和长链菊粉及中筋面粉为原料,采用差示量热扫描仪(DSC)和核磁共振仪(NMR)分析了不同聚合度菊粉在不同添加量(0、2.5%、5.0%、7.5%、10.0%)时对面团中可冻结水(弱结合水和自由水)和不可冻结水(紧密结合水)的影响。DSC结果表明:3种不同聚合度菊粉的添加均引起面团中可冻结水含水率的下降和不可冻结水含水率的上升;NMR结果表明:随着菊粉添加量的增加,面团中紧密结合水和自由水含水率增大,弱结合水含水率减小,说明菊粉的添加促进了蛋白质与水分的相互作用,而抑制了淀粉与水分的相互作用。短链和天然菊粉对面团中自由水的影响较明显,而长链菊粉则对紧密结合水的影响较明显,3种菊粉都对弱结合水的影响较明显。分析显示DSC与NMR测得面团中水分状态的结果具有一致性,面团中水分迁移行为与菊粉添加量之间存在显著的线性相关性。

Effect of Inulin on Moisture Migration Behavior in Wheat Dough

In order to investigate the influence of inulin on water migration in wheat dough, the freezable water (loosely bound water and free water) and non freezable water (tightly bound water) of wheat dough with different addition proportions (0, 2.5%, 5.0%, 7.5% and 10.0%) of short-chain, natural and long-chain inulin were determined by using differential scanning calorimetric (DSC) and nuclear magnetic resonance (NMR) techniques. The results of DSC showed that inulin with different degrees of polymerization (DP) all decreased freezable water content and increased non-freezable water content. And the effect of long-chain inulin on freezable water content was the most obvious. NMR results showed that with the increase of three kinds of inulin added, the contents of tightly bound water and free water were all increased in the dough, while the loosely bound water content was reduced, suggesting that the addition of three types of inulin all promoted the interaction between protein and water and inhibited the interaction between starch and moisture. The short-chain inulin and natural inulin had more obvious impact on the content of free water of the dough. On the other hand, the long-chain inulin had more significant influence on the content of tightly bound water; three kinds of inulin all had obvious effect on the loosely bound water content. In addition, the results of water state in the dough measured by DSC and NMR were consistent; there was a significant correlation between water migration and inulin addition. The test could provide data references for studying water distribution during the making process of dough and adjusting the product processing technology.