MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Lab of Meat Processing and Quality Control, MOE, Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Key Laboratory of Meat Products Processing, MOA, Nanjing Agricultural University, Nanjing 210095, China.
College of Science, Nanjing Agricultural University, Nanjing 210095, China.
Food Chem. 2019 Mar 1;275:770-777. doi: 10.1016/j.foodchem.2018.09.141. Epub 2018 Sep 27.
The effects of insoluble dietary fiber (IDF) on heat-induced gelation properties, such as microstructural changes and the molecular conformation of myofibrillar proteins (MP), were analyzed by image analyses and Raman spectroscopy. Scanning electron microscopy revealed that pure MP gelation contained a loose and dispersed network with interconnected water channels. With IDF addition, the lacunarity and the particle size of water pores both significantly decreased (P < 0.05) and fractal dimension significantly increased (P < 0.05), which indicated the formation of a homogenous and compact three-dimensional network. Through Raman spectra, IDF addition resulted in modification of amide I and III regions, by a significant decrease in α-helix content, accompanied by an increase of β-sheets, β-turns, and random coil content (P < 0.05); the intensity of CU+005CH stretching vibrations bending vibrations bands were significantly decreased (P < 0.05). Principal component analyses showed significant correlations between textual property, microstructure and molecular conformations. Cluster analyses indicated IDF improved the functionality of MP gel by 1): IDF stable the moisture phase 2) "concentrated" MP promoted structural integrity and compact gelation.
不溶性膳食纤维 (IDF) 对肌原纤维蛋白 (MP) 的热诱导凝胶特性，如微观结构变化和分子构象的影响，通过图像分析和拉曼光谱进行了分析。扫描电子显微镜显示，纯 MP 凝胶具有松散分散的网络结构，其中含有相互连通的水通道。添加 IDF 后，水孔的连通性和粒径均显著减小（P<0.05），分形维数显著增加（P<0.05），表明形成了均匀致密的三维网络。通过拉曼光谱，添加 IDF 导致酰胺 I 和 III 区域的修饰，α-螺旋含量显著降低，同时β-折叠、β-转角和无规卷曲含量增加（P<0.05）；CU+005CH 伸缩振动弯曲振动带的强度显著降低（P<0.05）。主成分分析表明，文本特性、微观结构和分子构象之间存在显著相关性。聚类分析表明，IDF 通过以下方式改善了 MP 凝胶的功能：1）IDF 稳定水分相；2）“浓缩”MP 促进了结构完整性和致密凝胶化。
