title: Influence of denaturation and aggregation of β-lactoglobulin on its tryptic hydrolysis and the release of functional peptides.
abstract: Whereas previous studies showed that thermal pre-treatment of whey proteins promote their enzymatic hydrolysis, to date no correlation between the conformation of denatured protein and the release of individual peptides has been considered. Hence, in this study total denaturation of β-lactoglobulin was performed at defined pH-values to enable the generation of different denatured particles. The denatured proteins were used as substrate for tryptic hydrolysis and the hydrolysis progress was characterised by the degree of hydrolysis (DH) and the release of functional peptides, detected using LC-ESI-TOF/MS. Denaturation and subsequent aggregation of β-lactoglobulin, induced by thermal treatment at pH 5.1, altered the DH slightly, whereas the release of investigated peptides was significantly decreased. Contrary, denaturation at pH 6.8 and 8.0 led to formation of non-native monomers and reduced the DH to 75%, but showed promoting as well as reducing effects on the release of peptides, depending on their location within the protein.
authors.affiliation: Technische Universität München, Chair for Food Process Engineering and Dairy Technology, ZIEL Research Centre for Nutrition and Food Sciences, Weihenstephaner Berg 1, 85354 Freising-Weihenstephan, Germany. Electronic address: elena.leeb@tum.de.
authors.forename: Elena
authors.initials: E
authors.lastname: Leeb
authors.affiliation: Technische Universität München, Chair for Food Process Engineering and Dairy Technology, ZIEL Research Centre for Nutrition and Food Sciences, Weihenstephaner Berg 1, 85354 Freising-Weihenstephan, Germany; Technische Universität München, Fakultät für Physik E14, Maximus-von-Imhof-Forum 4, 85354 Freising, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Götz
authors.affiliation: Technische Universität München, Analytical Research Group, Chair of Urban Water Systems Engineering, Am Coulombwall 8, 85748 Garching, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Letzel
authors.affiliation: Technische Universität München, Chair for Food Process Engineering and Dairy Technology, ZIEL Research Centre for Nutrition and Food Sciences, Weihenstephaner Berg 1, 85354 Freising-Weihenstephan, Germany; Global Applied Science & Technology (GAST), Mars GmbH, Eitzerstr. 215, D-27283 Verden, Germany.
authors.forename: Seronei Chelulei
authors.initials: SC
authors.lastname: Cheison
authors.affiliation: Technische Universität München, Chair for Food Process Engineering and Dairy Technology, ZIEL Research Centre for Nutrition and Food Sciences, Weihenstephaner Berg 1, 85354 Freising-Weihenstephan, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kulozik
mesh_terms: D006358:Hot Temperature; D006868:Hydrolysis; D007782:Lactoglobulins / Q000737:chemistry*; D013058:Mass Spectrometry; D010455:Peptides / Q000737:chemistry*; D011489:Protein Denaturation; D000067816:Whey Proteins / Q000737:chemistry
chemical_list: D007782:Lactoglobulins; D010455:Peptides; D000067816:Whey Proteins
keywords: Bioactive peptides; Denaturation of β-lactoglobulin; Non-native monomers; Protein hydrolysis; Trypsin