Heating-induced gel and rheological properties of tuna myofibrillar protein

The gelation characteristics of myofibrillar proteins are indicative of fish product texture.Gaining an additional insight of the gelation mechanism of tuna meat gel system was beneficial for the development of processed tuna products as well as maintaining quality in meat products.The effect of NaCl concentration (0.3 ～0.6mol/L) , on tuna myofibrillar protein gelation and rheological properties were studied using dynamic oscillatory rheometer of both small-amplitude oscillatory shear (SAOS) and large-amplitude oscillatory shear (LAOS) .The results showed that during the gel heating-induced process, the G ' of myofibrillar protein increased with the increase of NaCl concentration before 47℃.But this general trend changed after 47℃, G' reached a maximum value at NaCl concentration 0.4mol/L.The influence of NaCl was stronger during the period of gel formation.The relationship between its storage modulus and strain within could be described by the logarithmic model.The LAOS tests showed that the higher NaCl concentration would bring closer network structure and larger energy dissipated (Ed) during a sinusoidal stress cycle.The higher NaCl concentration would be able to hold linear viscoelasticity steadily.