Valorization of discarded egg whites as additives for sustainable mudbrick manufacturing: Technical and environmental evaluation

Mudbricks offer environmental advantages over fired bricks due to low embodied energy and absence of kiln firing, but suffer from poor compressive strength, water susceptibility, and limited durability. This study investigates waste egg whites from food industry as a sustainable reinforcing agent for mudbricks. Sustainable mudbricks were prepared using 79-90 wt% soil, 7 wt% water, 3-7 wt% egg whites, and 7 wt% neutralizing agents (H 2 SO 4 , CaSO 4 .2H 2 O, or C 6 H 6 ). Specimens were air-cured for 28 days at 25 ± 2 °C; control bricks were kiln-fired at 900 °C. The optimal formulation (7 wt% egg white) achieved 5.47 MPa compressive strength—doubling the control (2.27 MPa)—with 1540.84 kg/m 3 dry density, 0.6% reduced water absorption, enhanced hardness (5.5), no efflorescence, and chemical stability. Cradle-to-site life cycle assessment revealed 98.87% lower environmental impact than fired bricks across 18 categories, demonstrating waste egg whites as a viable sustainable alternative for mudbrick production. • Use discarded egg whites to reinforce sustainable mudbricks. • Assessed technical, environmental, and chemical fit of egg whites for strength. • Performed LCA comparing mudbricks with fired bricks’ environmental impacts. • Egg whites enhanced physical, mechanical, microscopic, and eco performance. • Mudbricks can replace fired bricks, cutting CO 2 in construction.