ANSWER

Despite its insolubility and hydrophobic nature, vital wheat gluten absorbs approximately twice its dry weight of water to form a hydrated viscoelastic mass (Ortolan & Steel, 2017).

Reference

Ortolan, F., & Steel, C. J. (2017). Protein Characteristics that Affect the Quality of Vital Wheat Gluten to be Used in Baking: A Review. Comprehensive Reviews In Food Science And Food Safety, 16(3), 369-381. https://doi.org/10.1111/1541-4337.12259