Plant-based proteins as functional egg replacers in pound cake: a comparative study of legume and oat ingredients

Rising demand for plant-based egg alternatives is caused by the need for sustainable, ethical and allergen-free solutions to conventional egg use in food systems. A systematic comparison was conducted on fourteen plant protein ingredients, including faba bean, lentil, chickpea and oat protein isolates, concentrates and flours, as egg replacements in pound cake formulations. Key properties assessed included foaming capacity and stability, protein solubility, emulsification, sulfhydryl content, water- and oil-holding capacity and minimum gelling concentration, alongside cake quality metrics such as batter rheology, bake loss, specific volume and crumb texture. Results revealed marked differences among protein sources, with faba bean (FPF) and lentil (LPF) flours demonstrating high protein solubility (FPF: 83.46 ± 0.35; LPF: 79.56 ± 0.23%) and favourable specific volume (FPF: 2.13 ± 0.03; LPF: 2.18 ± 0.03 mL/g), chickpea protein concentrate (CPC) contributing desirable springiness (0.86 ± 0.03) and cohesiveness (0.60 ± 0.02) and oat flours (OPF, OPFF, OF) providing notable emulsification stability (OPF: 0.52 ± 0.07; OPFF: 0.53 ± 0.07; OF: 0.54 ± 0.05%/min) and gelling capability (OPF/OPFF/OF: 8%). While none of the plant protein ingredients fully matched the multifunctionality of eggs, several demonstrated encouraging textural properties within this pound cake model, highlighting promising potential for further optimisation. The findings emphasise the importance of ingredient selection, processing, and potential protein blending or modification to improve the performance of plant-based egg replacers, without yet achieving egg-like multifunctionality. Overall, this work refines practical understanding of how compositional and techno-functional differences among legume- and oat-based ingredients translate into pound cake quality, and outlines opportunities for future, more targeted formulation strategies.