Effect of various types of egg white on characteristics and gelation of fish myofibrillar proteins.

Three types of egg white protein (regular dried egg white [REW], special dried egg white [SEW], and liquid egg white [LEW]) were compared for their effect in surimi (CON), containing no egg white (EW). They were characterized for enzyme inhibition and time of EW addition, either with cryoprotectants prior to freezing or during gel preparation, using Pacific whiting surimi. In addition, the setting (suwari) effect and fish protein-EW protein interactions (dynamic rheological properties, total sulfhydryl groups, and fracture gel analysis) were evaluated using Alaska pollock surimi. After 12 mo frozen storage, adding 2% and 3% SEW to Pacific whiting surimi during chopping significantly (P < 0.05) increased the force and deformation values compared to adding the respective EW before freezing. The highest (P < 0.05) force (175.2 g) and deformation (9.0 mm) values after 12 mo were obtained when 3% SEW was added during chopping. Enzyme autolysis showed that addition of 2% EW protein was effective at inhibiting enzyme activity. During setting, adding 2% SEW maintained force (1047.4 g) and deformation (17.9 mm) values similar (P > 0.05) to CON (1055.1 g; 19.3 mm) and significantly (P < 0.05) better than 2% REW (666.1 g; 15.6 mm). Texture results corresponded well to other data where 2% SEW showed the lowest total sulfhydryl groups (48.3 mole/10(5) g), and higher elastic modulus (G'), which suggests improved protein interaction for gel formation. Overall, the addition of 2% to 3% SEW improved gel textural properties of Pacific whiting and Alaska pollock fish protein.