Okara is a byproduct of the soy milk industry containing valuable phytochemicals, called isoflavones, among other components (i.e., proteins, sugars, fibers, etc.). As a waste product, okara is an interesting source material for obtaining valuable chemicals, and knowledge of the behavior of such components in their complex matrix is a key step for design of a purification process. Six commercially available macroporous polymeric resins are investigated to measure and model the equilibrium properties of the adsorption of isoflavones, proteins, and total solids onto these resins. A new model is evaluated in which adsorption of isoflavones onto a protein layer is proposed describing the system isoflavones–resin XAD 4 better than a linear isotherm model. Parameters for both the linear model and the bilayer model are regressed and reported with their accuracy and correlated to the hydrophobicity of each of the isoflavones.
- defatted soybean flakes
- dietary fiber
- soy milk
Méndez Sevillano, D., Jankowiak, L., van Gaalen, T. L. T., van der Wielen, L. A. M., Hooshyar, N., van der Goot, A. J., & Ottens, M. (2014). Mechanism of Isoflavone Adsorption from Okara extracts onto Food-Grade Resins. Industrial & Engineering Chemistry Research, 53(39), 15245-15252. https://doi.org/10.1021/ie5026419