Sprouting-Driven Changes in Extraction Yield and Techno-Functional Attributes of Legume Aquafaba with Insights into Functional Applications

Abstract

Aquafaba, the cooking water from legumes, has become a versatile plant-based alternative to eggs in food applications due to its functional properties. This study investigates the impact of sprouting on the extraction yield and techno-functional properties of aquafaba derived from sprouted legumes. Response surface methodology (RSM-BBD method) was used to determine the optimal extraction ratio, which included 36 hours of sprouting, a 1:2.5 seed-to-water ratio, and a 10-minute cooking time. Sprouting significantly improved the compositional profile of aquafaba, with protein content measured at 1.489 ± 0.04 mg/mL, alongside a reduction in antinutritional factors. A comparative analysis was conducted between sprouted and non-sprouted legume aquafaba, assessing parameters such as density, yield, water recovery, viscosity, turbidity, dry matter content, optical properties, and acidity profiles. The study also measured compositional, foaming, and emulsifying properties to evaluate techno-functional characteristics. Results showed that sprouting significantly enhanced viscosity (3±0.30 Cp), protein content (1.489±0.04 mg/mL), and total phenolic content (5.29 ± 0.2 mg GAE/mL), as well as foam density (0.27±0.07). It also maintained a lower foam drainage volume of 9.3% and exhibited an antioxidant capacity of 89%. There was no significant difference in dry solids content or water recovery, as evidenced by similar optimal cooking times and seed-to-water ratios. Foaming capacity and stability increased by 41% and 13%, respectively. Emulsion activity improved for sprouted legume aquafaba (4.478 x 10^3), along with enhanced turbidity (3.182 x 10^3), while no significant differences were observed in emulsion stability (~81.2%). These findings confirm the potential of spouted legume aquafaba in vegan food applications.