Young Jin Choi

Reduced-oil, plant-based mayonnaise-like emulsions require formulation strategies that provide both interfacial stabilization and sufficient continuous-phase structure. In this study, pea protein isolate (PPI) and cellulose nanofibers (CNF) were combined to construct egg-free emulsions containing 30% (w/w) oil. The PPI concentration was fixed at 2% and the CNF concentration was varied from 0 to 2% to test whether structuring of the continuous phase can compensate for the bulk structure lost on oil reduction. The PPI-only emulsion remained fluid and showed visible serum separation during storage, indicating that PPI alone did not generate a mayonnaise-like semisolid matrix at this oil level. CNF incorporation promoted the transition from flowable emulsions to self-supporting semisolid systems, improved resistance to visible phase separation, and increased firmness, work of shear, apparent viscosity, viscoelastic moduli, and modulated post-shear viscosity recovery. Emulsions containing 0.25% CNF or higher showed no obvious visible separation during 28 days of storage, and 0.5% CNF marked the onset of weak semisolid behavior. At 2% CNF, the emulsion approached the steady-shear viscosity profile of commercial mayonnaise; however, it showed higher firmness and viscoelastic moduli, indicating greater deformation resistance rather than complete textural equivalence. These findings show that CNF-assisted continuous-phase structuring is an effective route to PPI-based reduced-oil mayonnaise-like emulsions. They also show that matching apparent viscosity alone is insufficient, and that CNF concentration must be balanced against physical stability, spreadability, viscoelasticity, and post-shear recovery.

Plant-based mayonnaise alternatives require structuring strategies that reproduce the rheological and textural characteristics of high-fat emulsions without the need for addition of animal-derived emulsifiers. Here, emulsion gels containing 2 wt.% soy protein isolate and 0.5 wt.% cellulose nanofibers (CNFs) were prepared to examine the way in which the oil concentration (30–70%) influenced structure formation. Increasing the oil content induced a transition from weak, droplet-dispersed systems (30–50%) to more structured, gel-like systems within a narrow oil concentration window (60–65%), where smaller and more uniformly distributed droplets were observed in addition to increases in viscoelasticity, structural recovery, and firmness comparable to those of commercial mayonnaise. At 70% oil, droplet coalescence and phase separation indicated loss of structural integrity. These results identified an intermediate oil concentration window in which mayonnaise-like structuring was most evident, highlighting the role of CNF-containing aqueous phases in supporting droplet packing and structural organization in protein-based emulsion gels.

This study investigated the role of the degree of polymerization (DP) and the inclusion level of cellulose in governing the anisotropy and texture of soy protein isolate-based high-moisture meat analogs. Low-DP cellulose offered modest reinforcement, leading to a slight increase in hardness and limited enhancement of fibrous alignment. In contrast, high-DP cellulose markedly increased hardness and chewiness with increasing loading, while springiness and cohesiveness were unaffected. At 3% high-DP cellulose, the texturization index peaked with highly aligned lamellae, whereas 5% further stiffened the network but reduced anisotropy due to over-consolidation. Fourier transform infrared spectroscopy confirmed a transition from coil/helix to β-sheet structures, peaking at 3% high-DP cellulose. Chemical probing revealed progressive gains in hydrogen bonding and hydrophobic interactions, with disulfide bonds exhibiting a maximum under the same condition. Overall, cellulose chain length dictates function: low-DP densifies, and high-DP aligns and reinforces, with ≈3% high-DP cellulose optimal for anisotropic fibrous networks.