Abstract: This study investigated the application of combinations of different amounts (0.0%, 1.0%, 1.5%, 2.0% and 2.5%) of porcine fibrinogen with 2.0% plasma protein, 0.3% compound phosphate, 0.5% NaCl, and 4.0% water as a binder in restructured beef. The effects of fibrinogen concentration on the color parameters (L*, a* and b*), water activity and thawing loss of restructured beef were studied, and the binding strength was measured with a texture analyzer as a function of fibrinogen concentration and binding time. Besides, the mobility of water molecules during the binding process was examined by low-field nuclear magnetic resonance (LF-NMR). The microscopic structure of restructured beef made with tansglutaminase (TG) and fibrinogen as a binder was investigated by scanning electron microscopy (SEM). The results showed that increasing the fibrinogen concentration could slightly reduce water activity without statistical significance (P > 0.05), significantly decrease thawing loss (P < 0.05), significantly increase color a* value (P < 0.05), and lower color L* value. The binding strength significantly increased with increasing binding time in the tested range (P < 0.05). At the same time, the results of LF-NMR showed that fibrinogen could increase the mobility and binding of water molecules in restructured beef. SEM examination showed that fibrinogen provided more compact microstructure of restructured beef than TG. Therefore, fibrinogen can be used as a binder in restructured beef.

Key words: fibrinogen, plasma protein, compound phosphate, low-field nuclear magnetic resonance (LF-NMR)