Dry soybean (Glycine max) residue (SBR) is a byproduct rich in dietary fibre and protein with high levels of essential amino acids. The effects due to the substitution of refined wheat flour with 5% or 10% SBR in dough rheology and hot-press tortilla texture, dimensions, colour, protein and dietary fibre contents were studied. Substitution of 10% SBR improved flour in terms of gluten strength and sedimentation without significantly affecting dough hardness, cohesiveness, adhesiveness, and extensibility. The dimensions, colour and sensory acceptance of the supplemented tortillas were not affected by the addition of the SBR. The 10% SBR tortillas contained 1.77 times more insoluble dietary fibre, protein content of 9.3%, in vitro protein digestibility of 84% and protein digestibility corrected amino acid score (PDCAAS) of 52.63%. Results indicated that wheat flour tortillas with 10% SBR an excellent alternative to regular counterparts owing to their higher dietary fibre and protein quantity and quality.

Background and objectives Nixtamalized dry masa flour was supplemented with 5% or 10% dry soybean bagasse (SB) and then processed into table tortillas. Proximate chemical composition, dietary fiber content, affective sensory analyses of corn tortillas prepared from dry masa flour enriched with 5% or 10% dried SB were determined. Also, the in vitro protein digestibility and protein digestibility‐corrected amino acid score (PDCAAS) of the tortillas were evaluated. Findings Ten per cent SB addition reduced masa hardness by about 32% and chewiness 47% without affecting adhesiveness. In terms of rapid viscosity analysis, the addition of incremental levels of SB decreased peak and final viscosities 42% and 49%, respectively. The tortilla insoluble and soluble dietary fiber contents increased 50% and fourfold, respectively, while the lysine daily requirement for preschool infants improved from 45.6% to 67.0% when 10% SB was used. Enriched tortillas showed a similar overall acceptance and had improved texture over storage time at room temperature (25% less force to rupture compared with the control tortilla stored for the same time). Conclusions The addition of 5% soybean bagasse to nixtamalized corn flour produced masa with good machinability and tortillas with better overall acceptance and textural shelf life and a product with four times more soluble dietary fiber, 10% less starch and with higher amounts of limiting amino acids lysine and tryptophan. The upgraded amino acid balance significantly improved PDCAAS from 41% to 59% in the tortilla containing 10% SB. Significance and novelty Soybean bagasse is a viable option to increased fiber and protein quality in nixtamalized corn flour tortillas, with a positive impact on texture during shelf life and consumer acceptance.