Described is a composition of peptides resulting from heat-induced acidic hydrolysis or enzymatic hydrolysis of a protein selected from the group consisting of β-lactoglobulin-containing whey protein preparation, glycinin-containing soy bean protein preparation, patatin, and mixtures thereof. The composition is capable of fibrillary aggregation upon subjection to acidic pH Thus a pre-fibril composition is provided that has a variety of uses. Thus, they can be used to form fibrils that, in turn, have various structuring and water-retention uses, or they can be used as a food or non-food additive per se. A particular benefit is obtained in human or animal diet foods for weight-control, as the peptide prefibrils will not substantially effect a foods taste or mouthfeel, while fibrillary aggregation in gastric juice will increase satiation.
