利用低场核磁共振技术测定肌原纤维蛋白凝胶的保水性及其水分含量

Water-holding Capacity and Water Content of Myofibrillar Protein Gel by Low-field Nuclear Magnetic Resonance

摘要:

本研究借助低场核磁共振技术研究蛋白凝胶的保水性及水分含量，并通过传统干燥法进行验证。结果表明：通过低场核磁共振测定肌原纤维蛋白凝胶的横向弛豫时间T2，研究凝胶中结合水、不易流动水和自由水3种状态水的组成及分布，自由水百分含量越高，其保水性越低，总水分含量越高；借助核磁共振成像得到凝胶中水分子氢质子密度图谱可直观反映凝胶的水分含量及空间分布情况，质子密度图灰度值越高，凝胶水分含量越高；传统干燥法的测定结果结合相关性分析表明低场核磁共振测得凝胶的不易流动水、自由水及灰度值与传统干燥法测得凝胶总水分含量相关系数分别为0.96、0.96、0.97，且均达到显著水平（p<0.05）。综上所述，低场核磁共振技术能用于研究肌原纤维蛋白凝胶的保水性及其水分含量。

Abstract:

Low-field nuclear magnetic resonance (NMR) and traditional drying method were analyzed to determine water holding capacity (WHC) and water content of myofibrillar protein (MP) gel. The results showed that determination of the spin-spin relaxation time (T2) of MP gel could reflect the compositions and distributions of the three states of water (bound water, immobile water and free water) in MP gel. The higher the free water percentage, the lower the WHC and the higher the water content. The proton density images of MP gels were obtained by magnetic resonance imaging (MRI), which could reflect the content and spatial distribution of water in MP gels. The higher the grey value of proton density image, the higher the water content of MP gel. Pearson’s correlation analysis showed that the grey value, the contents of immobile and free water that measured by low-field NMR were significantly correlated with the results that measured by the traditional drying methods (p<0.05), and the correlation coefficient were 0.97, 0.96 and 0.96, respectively. In conclusion, the low-field NMR technique can be used to determine WHC and water content of MP Gel.