Insight into the mechanism of fracture properties modulated by microstructure in the myofibrillar protein and polysaccharide gel systems

The objective of this study was to investigate the mechanism of fracture properties modulated by microstructure in the myofibrillar protein (MP) and polysaccharides gel systems. Compare to the modified starch, the dietary fiber significantly improved the fracture stress and reduced the fracture strain at same concentration. The treatment with 2% dietary fiber had the highest value of fracture stress and the lowest value of fracture strain, which were 259 g and 1.12 respectively. From the skeleton structure, the Raman spectroscopy result showed that dietary fiber addition significantly reduced the intensity at 2945 cm(-1), which suggested that the aggregation of hydrophobic groups was improved. The SEM showed that the treatment with 2% dietary fiber had the highest fractal dimension value of 1.7772 and the lowest lacunary value of 0.258. From the filling structure, the paraffin section showed that the polysaccharides were just simply trapped in MP gel networks and formed numerous large volumes and no-elastic of cavities. The principal component analysis suggested that the compactness of three-dimensional gel networks determined fracture stress of composite gel. The no- no-elastic of cavities formed by modified starch and dietary fiber resulted in the reduction of fracture strain. These results would promote the development of innovative nutritional meat product formulation with satisfied textural property.