A new pathway of lactose degradation and arginine derivatization in milk
E. Mavric, T. Henlehttps://doi.org/10.17221/10624-CJFSCitation:Mavric E., Henle T. (2004): A new pathway of lactose degradation and arginine derivatization in milk. Czech J. Food Sci., 22: S93-S95.
Abstract: Recently, N-δ-[5-(3-hydroxypropyl)-4-oxo-imidazolon-2-yl]--ornithine (PIO) was identified as a new arginine derivative, formed exclusively from the side-chain of peptide-bound arginine and degradation products of oligosaccharides with 1,4-glycosidic linkages, thus probably representing the major form of arginine derivatization in heated milk products. The formation mechanism of PIO was clarified via identification of a previously unknown C5 dicarbonyl precursor, namely 3,4-dideoxypentosulose (3,4-DDPs). 3,4-DDPs was isolated as the corresponding chinoxaline from reaction mixtures containing N-α-hippuryl arginine, lactose and o-phenylendiamine using semipreparative RP-HPLC. Identification was achieved using LC-MS as well as 1H- and 13C-NMR. The formation of 3,4-DDPs from lactose follows a new pathway of carbohydrate degradation in foods.
arginine derivatization; lactose; 3,4-dideoxypentosulose; Maillard reaction