Assessing the digestibility and estimated bioavailability/ bioaccessibility of plant-based proteins and minerals from soy, pea, and faba bean ingredients

Concerns have been raised about the nutritional adequacy of plant-based foods due to the presence of antinutrients and overall low protein digestibility. Therefore, this study characterizes the estimated bioavailability/ bioaccessibility of iron and zinc and the protein digestibility of 11 commercially available plant-based ingredients to assess their potential in the future development of nutritious plant-based foods. The accessibility of iron and zinc was limited in all ingredients, with only faba bean isolate, pea isolate, faba bean concentrate and texturized pea containing accessible iron. Faba bean isolate was found to have the highest amount of accessible iron (67.4 mg/kg) whereas textured pea showed the lowest amount (0.5 mg/kg). The estimated bioavailability of iron and zinc, based on the calculated molar ratio of phytate, was low for all studied ingredients, with isolates showing the highest overall tendency for available iron and zinc. The amino acid composition data revealed limitations regarding valine and/or isoleucine in all protein concentrates and texturized proteins, soy isolate, and faba bean flour. In contrast, no significant differences were found in overall protein digestibility, suggesting that all tested raw materials, including faba bean, can be considered good protein sources.