Physicochemical, techno-functional, and in vitro gut microbial fermentation characteristics of Cyperus esculentus protein benchmarked against soy protein isolate.

BACKGROUND: The increasing demand for sustainable dietary proteins has driven interest in alternative plant-derived ingredients beyond soy protein. Although soy protein isolate (SPI) remains widely used, its supply is affected by trade dependence and price fluctuations. Cyperus esculentus protein (CEP), recovered from underutilized tiger nut by-products after oil extraction, may improve resource efficiency and support value-added utilization. However, its techno-functional properties and gut microbial fermentation behavior remain insufficiently characterized under direct comparison with SPI. RESULTS: Compared with SPI, CEP showed favorable emulsifying and foaming properties, a relatively small median particle size (D50 = 40.32 μm), and good thermal stability. CEP also exhibited a balanced amino acid profile, with hydrophobic amino acids accounting for 31.68% ± 0.83% of total amino acids. During in vitro gut microbial fermentation, CEP enriched genera including Agathobacter, Bacteroides, and Butyricicoccus. After 24 h, acetate, propionate, and butyrate concentrations reached 13.00 ± 0.27, 11.95 ± 0.18, and 10.20 ± 0.47 mmol L-1, respectively, all significantly higher than those in the control group. CONCLUSION: CEP combines competitive techno-functional performance, favorable amino acid composition, and promising fermentability, indicating its potential as a sustainable and value-added plant-protein ingredient. © 2026 Society of Chemical Industry.