Polyether polyols as GPC calibration standards for determination of molecular weight distribution of polyether polyols

Inulin for surimi gel fortification: Performance and molecular weight-dependent effects

Inulin is a prebiotic carbohydrate widely used in food industry due to its health benefits and unique rheological properties. For the first time, this study explores the potential of natural inulin as a sustainable food additive to enhance surimi gel characteristics, specifically focusing on understanding its molecular weight effects. The good solubility of inulin facilitates the conversion of α-helix to other secondary conformations which are favorable for protein denaturation and aggregation during gelation. Moreover, the abundant -OH groups at the surface of inulin can boost the chemical forces within surimi proteins to reinforce the gel network. Compared to short-chain inulin, long-chain inulin can alleviate proteolysis, enhance hydrophobic interactions and intertwine with myosin molecules, thereby reinforcing the gel network. A more viscous long-chain inulin solution formed within surimi gels fills the space between aggregated proteins and facilitates the lock of water molecules, improving the water-holding capacity (WHC). Thus, an addition of 12 % long-chain inulin leads to an enhanced hardness of surimi gel from 943 to 1593 and improved WHC from 72 % to 85 %. A new inulin-myosin interaction mechanism model is also proposed to provide useful guidelines for surimi processing and expanding the application of inulin within the food industries.

Structure–property performance of natural palm olein polyol in the viscoelastic polyurethane foam

Structure–property behavior of the palm olein-based natural oil polyol (E-135 NOP) was investigated in viscoelastic “memory” foams. In a model viscoelastic foam formulation, the E-135 NOP with pendant hydroxyls was used as a drop-in replacement for the well-defined model polyether polyol with terminal hydroxyls, Poly-G® 76-120. Both polyols have comparable equivalent weight and concentrations of primary and secondary hydroxyls. The data showed that replacing Poly-G® 76-120 polyether polyol with the E-135 NOP did not significantly impact the foaming reactivity. Increasing the E-135 NOP concentration in the VE foams increased the average foam cell size while maintaining the open cell structure. Aging properties of the VE foams were mostly unaffected by the replacement of the Poly-G® 76-120 with the E-135 NOP. Furthermore, addition of E-135 had no impact on foam density; however, it increased the support factor of the viscoelastic foams. Differential scanning calorimetry, dynamic mechanical analyzer, and Fourier transform infrared spectroscopy analyses indicate less defined morphological separation of hard and soft segments in the viscoelastic foams with higher concentration of E-135 NOP. Overall, the results demonstrated the feasibility that natural oil polyols can be used in viscoelastic polyurethane foams to replace a significant portion of the polyether polyols with comparable equivalent weights and concentrations of primary and secondary hydroxyls. In future, the feasibility study of E-135 NOP as a drop-in replacement of combination polyether polyols in viscoelastic foams formulation will be conducted. Furthermore, the effect of palm olein-based natural oil polyol in high resilience foam will be evaluated.