Starch nanocrystals (SNCs) derived from rice starch were complexed with soybean β-conglycinin (7S) or glycinin (11S) to develop food-grade Pickering emulsifiers for curcumin delivery. The effects of the SNC-to-protein mass ratio on particle structure, interfacial properties, emulsion stability, and gastrointestinal digestion were systematically evaluated. At an SNC-to-protein mass ratio of 1:1, the SNCs-7S and SNCs-11S complexes exhibited the smallest particle sizes of 110 ± 4 and 234 ± 6 nm, respectively. Their three-phase contact angles approached 90°, indicating favorable interfacial wettability. SNCs induced concentration-dependent fluorescence quenching of 7S and 11S, with maximum quenching efficiencies of 61.02 ± 1.41% and 37.51 ± 1.09%, respectively. Raman spectroscopy and molecular docking analyses indicated that complex formation involved rearrangements of the protein secondary structure and hydrogen bonding. All calculated binding energies were below -6.0 kcal/mol, with the lowest value of -6.5 kcal/mol observed for SNCs-11S. Pickering emulsions containing 60% soybean oil exhibited shear-thinning and predominantly elastic behavior (G' > G″). The 1:1 composite systems formed the strongest network structures and exhibited no evident creaming, flocculation, or oiling-off after storage at 4 °C for 30 days. The SNCs-7S emulsion achieved a curcumin encapsulation efficiency (EE) and loading capacity of 90% and 7.5%, respectively, exceeding the corresponding values of 86% and 6.0% obtained for the SNCs-11S emulsion. After intestinal digestion, free fatty acid release from the SNCs-7S and SNCs-11S emulsions reached 46.31 ± 2.71% and 40.68 ± 0.71%, respectively. Overall, the 1:1 SNCs-7S system exhibited the most favorable interfacial assembly, storage stability, curcumin encapsulation, and lipid digestibility.
Yuan Wang, Yang Yang, Yue Xu et al.· International Journal of Bio...· 0 citations
The global trend toward low-fat diets is creating a critical need for efficient fat replacement technologies. This study explored the stabilization behavior of soybean protein isolate (SPI)-citrus pectin (CP) Pickering emulsions and their effectiveness as butter substitutes in pound cakes. The results indicated that emulsions with 5% particle concentration (c) and 50% oil phase volume fraction (ϕ) exhibited excellent storage, centrifugal, thermal, and lipid oxidation stability. It also demonstrated superior structural and rheological properties, effectively replicating the physical characteristics of butter. Moreover, replacing butter with SPI-CP Pickering emulsion significantly enhanced the quality of pound cakes, with a 40% substitution level proving optimal. At this ratio, the specific volume increased by 21.01%, while hardness and chewiness decreased by 57.48% and 52.43%, respectively. Meanwhile, a decrease in fat migration capacity was observed, along with increases in in vitro cholesterol adsorption capacity and sodium cholate adsorption capacity. Electronic nose analysis confirmed similar aroma profiles, and sensory evaluation yielded the highest scores, indicating that the SPI-CP-stabilized emulsion effectively maintained cake quality while serving as a butter alternative. This study offers valuable insights for developing low-fat foods and novel functional ingredients.
Yang Yang, Huixin Zheng, Yue Xu et al.· Food Research International· 0 citations
Despite the advantageous functional properties of soybean protein isolate (SPI), its inherent conformation is susceptible to environmental influences, thereby limiting its utility in food systems. This work investigated the effect of mass ratio between soybean protein isolate (SPI) and citrus pectin (CP) on the structure and functionality of composite particles. Results showed that a 1:1 SPI-to-CP ratio produced the smallest particle size (280.13 nm) and the best dispersion stability. This ratio also significantly improved emulsifying activity (EAI: 54.80 m2/g) and emulsion stability (ESI: 105.91%), while enhancing the adsorption capacity of interfacial proteins. The composite particles were driven by hydrogen bonding, hydrophobic interactions, and electrostatic forces. These interactions promoted the conformational unfolding of SPI, increasing surface hydrophobicity and facilitating a structural transition from α-helix to β-sheet. This work provides fundamental insights for designing food-grade particles with enhanced interfacial activity and stability.
Yang Yang, Xiao-ning Wang, Yue Xu et al.· Food Chemistry· 0 citations