A protein-enriched by-product derived from the Bioraf oil extraction procedure applied to rapeseed has been enzymatically hydrolyzed by Alcalase and subsequently acylated using C6–C16 acyl chlorides to generate modified hydrolysates with good foaming properties. The resulting peptides had an average size of 5.4 amino acids, and their degree of acylation ranged from 68 to 94% of amino groups. The better foaming properties were obtained with C10- and C12-acylated hydrolysates, whereas the modification using shorter (C6 and C8) or longer (C14 and C16) aliphatic chains led to unstable foams. C10- and C12-acylated peptides were preferentially adsorbed at the air/liquid interface and formed foams with a texture more stable than that of those prepared using sodium dodecyl sulfate (SDS) or bovine serum albumin (BSA), used as standard foaming agents. Such foams were characterized by a rather low amount of liquid incorporated into the foam, but their bubble density was more homogeneous during aging than that of SDS or BSA. Similarities to SDS in terms of a rapid drainage of liquid and dry aspects of the foam, and with BSA concerning the maximal volume of liquid incorporated in the foam, suggest that acylated peptides exhibit foaming behavior between surfactants and proteins.