Fat blocking roles of fish proteins in fried fish cake

This study evaluated the physicochemical properties of fried surimi gel formulated with konjac glucomannan (KJ) and coated with surimi slurry coating. When 0.25% KJ and 0.5% KJ were combined with surimi slurry coating, total fat content was reduced by 33.59% and 62.57%, respectively, compared to the control. The results suggested that hydrophilic compounds (konjac and sugar/sorbitol in surimi) possibly played a significant role in repelling fat molecules from the surface of surimi paste. The oil transport tests demonstrated higher fat absorption in the crust of fried fish cake compared to the core region. SEM analysis measuring texture images confirmed that surimi slurry coating provided a smooth surface and the addition of KJ provided a homogeneous and denser texture with reduced number of voids in the core layers. As dynamic rheology explored, the entire surimi paste was gelled thermally during frying, resulting in a filmed surface. Thereby the film reduced water evaporation and would have minimized fat uptake. In summary, the fat blocking phenomenon by fish proteins mixed with KJ was attributed by hydrophilic compounds (sugar/sorbitol from surimi and KJ) that possibly dispelled fat globules during frying and the subsequent formation of filmed surimi gel, significantly minimizing the absorption of fat.