Dynamic rearrangement of disulfide bridges influences solubility of whey protein coatings

In this study, the mechanism governing the solubility of whey protein films and coatings was investigated. The building blocks for these films and coatings were aggregated whey proteins. Solubility was related to the continuity of the network of disulfide cross links between the building blocks and the dynamics of rearrangements of disulfide bonds occurring via the so-called thiol–disulfide exchange reaction. By controlling either the accessibility of thiol groups or the accessibility of disulfide bonds within the whey protein aggregates, solubility of whey protein coatings and films could be tuned. These new insights will help improving the properties of protein coating, promoting the applicability of whey proteins in films, encapsulates and coatings.