Cottonseed protein fibrils: A plant-based foaming agent outperforming egg white

The food industry faces mounting challenges in sourcing sustainable, plant-based alternatives to animal-derived foaming agents that meet both functional and ecological demands. This study introduces cottonseed protein fibrils (CSPF) as a high-performance substitute for egg white proteins through controlled fibrillization of cottonseed protein. Structural characterization revealed that optimized processing conditions (pH 2.0, 90 °C, 12 h) promoted the formation of amyloid-like fibrils with cross-β structure, as verified by Thioflavin T fluorescence, atomic force microscopy, and X-ray diffraction analyses. Remarkably, CSPF demonstrated exceptional foaming capacity and stability, achieving a 947.3 % overrun (compared to 733.5 % for egg white) and superior stability with only 18.6 % drainage (versus 73.8 % for egg white). Mechanistic studies attributed this superior performance to the synergistic effects of increased surface activity and improved interfacial viscoelasticity. Practical validation in meringue production confirmed CSPF's technological feasibility, positioning it as a sustainable solution that leverages underutilized oilseed proteins.