Co-folding scallop muscle proteins with soy β-conglycinin or glycinin towards composites with tunable solubility and digestibility

Edible proteins with high solubility, designable nutritional properties and tunable digestibility are attractive. Scallop muscle proteins (SMPs) are representative marine proteins, which have a poor water-solubility and thus inferior solubility-related physicochemical properties. Here, by unfolding SMPs and soy proteins at pH 12.0 followed by shifting to pH 7.0 to refold them together, soluble composite structures were formed, characteristic of uniform nanospheres with a diameter of similar to 100 nm. Owing to embedment of hydrophobic pockets whereas exposure of hydrophilic moieties, the solubility of SMPs was enhanced from 26% to 91%, depending on the mass ratio of beta-conglycinin/glycinin (7S/11S). Furthermore, the digestibility of the composites can be delicately modulated by harnessing the same stimulus, which highlighted future design of edible proteins with controllable digestion. This study provides a robust and facile strategy for developing edible proteins with tailorable structures and structure-related functional and nutritional characteristics.