Gel properties and interactions of scallop (Patinopecten yessoensis) male gonad hydrolysates and nonionic polysaccharide mixtures.

• Scallop male gonad hydrolysates (SMGHs) have potential as gel matrix. • Synergistic effects between SMGHs and two nonionic polysaccharides were determined. • SMGHs and nonionic polysaccharides developed a hydrogel with exceptional viscosity. • Hydrogen bonding and hydrophobic interaction are dominant forces in the mixed gels. The involvement of hydrogen bonding and hydrophobic interactions in a mixture of scallop (Patinopecten yessoensis) male gonad hydrolysates (SMGHs) and guar gum (GG) or locust-bean gum (LBG) was investigated using guanidine hydrochloride (GuHCl) and urea treatments in this study. The addition of GG and LBG (5.56 mg/mL) increased the viscosity of SMGHs at 0.1 s-1 by almost 2.5-fold and 1.7-fold, respectively, reaching 254.8 and 177.0 Pa·s. After treatment with GuHCl or urea, the mixed gels (SMGHs/GG and SMGHs/LBG) became relatively transparent and more fluid, as the viscosity significantly reduced. Moreover, changes of moisture distribution and conformational characteristics suggested that hydrogen bonding and hydrophobic interactions were the main intermolecular forces in the mixed gels of SMGHs and GG or LBG. Furthermore, the SMGHs/GG and SMGHs/LBG mixtures yielded strong gels with viscous network structures, indicating that these materials can be used as thickening agents in food systems. [ABSTRACT FROM AUTHOR]