Silver Carp (Hypophthalmichthys molitrix) Surimi Acid-Induced Gel Extract Characteristics: A Comparison with Heat-Induced Gel

Traditional surimi-based products are usually prepared through a heating process, which often causes high energy consumption and increased production costs. Acid-induced surimi gel, as a new preparation technique, were prepared from silver carp surimi by soaking in acetic acid in this study, and their properties and formation mechanism were investigated and compared to heat-induced gel. The moisture content, breaking force, deformation, and whiteness of acid-induced surimi gel were all higher than those of heat-induced gel, irrespective of acid concentration. The textural properties, color values and water holding capacity of acid-induced gel were increased with acetic acid concentration increase from 1 to 3%. On the other hand, the high molecular weight fractions were also formed with myosin heavy chain based on electrophoresis analysis. The data of protein subunits solubilized in various solvents revealed that the most important associative force in acid-induced gel was hydrophobic interactions. Furthermore, the compact and fine fiber microstructure in acid-induced surimi gel was observed by scanning electron microscopy. It is concluded that a tri-dimensional network was formed within the acid induced surimi gel through hydrophobic interactions and disulfide bonds with the presence of myosin heavy chain and actin, resulting in formation of compact fine fiber microstructures.