Changes in texture and molecular forces of heated-induced egg white gel with adding xanthan gum

摘要

The effects of xanthan gum (XG; 0, 0.06, 0.12, and 0.18 wt%) on the formation of egg white (EW)-XG gels were investigated using modern instruments low-field nuclear magnetic resonance (LF-NMR), SEM, Fourier transform infrared (FTIR), and chemical analysis. Results showed that at low concentrations of XG (0.06 wt%), the hardness and springiness of gels were increased, while free sulfhydryl content and surface hydrophobicity declined. A rapid decrease (p .05) in T2 of EW gels was found as the XG increased, which effected on proton mobility and relaxation peak changeability of EW gels. Results from FTIR revealed that XG addition affected the secondary structure of EW gels by increasing the contents of beta-sheet due to the interaction among protein and XG. And a coarse structure of gel was observed at a high concentration of XG. These findings suggested that the presence of XG in heated-induced EW endowed a desired characteristics gel of EW for enlarging the applications. Practical applications Many food systems are in neutral environment, such as surimi products, egg tofu. Proteins and polysaccharides are two of the raw materials commonly used in food processing. Protein-polysaccharide hybrid gels have application in adjusting product formulations and improving the texture and quality of the product. However, we need to understand the gel texture properties and mechanisms before expanding specific utilization of hybrid gel, which provides a theoretical basis for designing new attractive structures and textures.