Sardine Sol and Sardine Gel Induced by Li Salt and HSCN Derivatives

Abstract

Unfolding protein structure by denaturant and rearranging intramolecular bonds to intermolecular bonds might be useful technique to generate proteins which exhibit new physical properties. From this viewpoint, some research was carried out to investigate if structured sardine products are feasible in both sol state and gel state. When the incubation of sardine paste (prepared from round sardine) in the presence of denaturant did not bring about any increase of viscoelasticity, the removal of denaturant by dialysis did not induce gelation. In this instance, 8_M LiBr was used a sadenaturant. When the incubation of sardine paste in the presence of denaturant did bring about the increase of viscoelasticity or the occurrence of gelation, the removal of denaturant by dialysis promoted gelation still more. In this instance, 4_M, 8_M NH₂C(=NH)NH₂HSCN, or 4_M NaSCN was used as a denaturant. The local unfolding of protein structure by 8_M LiBr induced sardine sol to be hydrated and viscous. The local unfolding of protein structure by 4_M NaSCN induced sardine gel made of coarse particles. The complete unfolding of protein structure by 4_M or 8_M NH₂C(=NH)NH2HSCN induced sardine sol easy to flow and sardine gel made of fine structure.