Whey protein isolate (WPI) has a variety of nutritional benefits. The stability of WPI beverages has attracted a large amount of attention. In this study, Flammulina velutipes polysaccharides (FVPs) interacted with WPI to improve the stability via noncovalent interactions. Multiple light scattering studies showed that FVPs can improve the stability of WPI solutions, with results of radical scavenging activity assays demonstrating that the solutions of the complex had antioxidant activity. The addition of FVPs significantly altered the secondary structures of WPI, including its α-helix and random coil. The results of bio-layer interferometry (BLI) analysis indicated that FVPs interacted with the WPI, and the equilibrium dissociation constant (K_D) was calculated as 1.736 × 10⁻⁴ M in this study. The in vitro digestibility studies showed that the FVPs protected WPI from pepsin digestion, increasing the satiety. Therefore, FVPs effectively interact with WPI through noncovalent interactions and improve the stability of WPI, with this method expected to be used in protein-enriched and functional beverages.

In this study, pine nut kernels from two grafted species: Pinus koraiensis (PK) and Pinus sylvestris var. (PKS) were roasted (130, 150, 180 ℃ for 10, 20, 30min) to investigate the effect of roasting pre-treatment on chemical components, antioxidant activity and oxidative stability of oils prepared from kernels. Increased temperature or time was found to cause significant increase in oil yield, color, total phenolic content (TPC), carotenoid and browning index (BI) of oils compared to unroasted samples. Roasting could also elevate the antioxidant activity and oxidative stability of pine nut oil. The levels of tocopherol decreased significantly at high temperature (150 ℃, 180 ℃), while the fatty acid compositions were almost independent of roasting conditions. The FTIR spectra of oils from different roasted pine nuts showed minor variation in peak intensities. Therefore, roasting is a great option and critical step to improve the quality of pine nut oil.