Title
Structure of mixed β-lactoglobulin/pectin adsorbed layers at air/water interfaces; a spectroscopy study
Author
Ganzevles, R.A.
Fokkink, R.
van Vliet, T.
Cohen Stuart, M.A.
de Jongh, H.H.J.
TNO Kwaliteit van Leven
Publication year
2008
Abstract
Based on earlier reported surface rheological behaviour two factors appeared to be important for the functional behaviour of mixed protein/polysaccharide adsorbed layers at air/water interfaces: (1) protein/polysaccharide mixing ratio and (2) formation history of the layers. In this study complexes of β-lactoglobulin (positively charged at pH 4.5) and low methoxyl pectin (negatively charged) were formed at two mixing ratios, resulting in negatively charged and nearly neutral complexes. Neutron reflection showed that adsorption of negative complexes leads to more diffuse layers at the air/water interface than adsorption of neutral complexes. Besides (simultaneous) adsorption of protein/polysaccharide complexes, a mixed layer can also be formed by adsorption of (protein/)polysaccharide (complexes) to a pre-formed protein layer (sequential adsorption). Despite similar bulk concentrations, adsorbed layer density profiles of simultaneously and sequentially formed layers were persistently different, as illustrated by neutron reflection analysis. Time resolved fluorescence anisotropy showed that the mobility of protein molecules at an air/water interface is hampered by the presence of pectin. This hampered mobility of protein through a complex layer could account for differences observed in density profiles of simultaneously and sequentially formed layers. These insights substantiated the previously proposed organisations of the different adsorbed layers based on surface rheological data. © 2007 Elsevier Inc. All rights reserved. Chemicals / CAS: beta lactoglobulin, 9045-23-2; Lactoglobulins; Membranes, Artificial; pectin, 9000-69-5; Pectins; Water, 7732-18-5
Subject
Healthy for Life
Nutrition
Healthy Living
Food technology
Adsorption
Fluorescence anisotropy
Neutron reflection
Polysaccharide
Protein
Adsorption
Fluorescence spectroscopy
Neutron reflection
Proteins
Rheology
Surface tension
Fluorescence anisotropy
Lactoglobulins
Mixing ratio
Polysaccharides
beta lactoglobulin
lectin
polysaccharide
adsorption
anisotropy
article
chemical structure
flow kinetics
priority journal
spectroscopy
Adsorption
Air
Animals
Cattle
Fluorescence Polarization
Lactoglobulins
Membranes, Artificial
Neutrons
Pectins
Scattering, Radiation
Spectrum Analysis
Surface Properties
Time Factors
Water
To reference this document use:
http://resolver.tudelft.nl/uuid:1438ed2b-1e06-4dc8-93b4-8fe51da43357
DOI
https://doi.org/10.1016/j.jcis.2007.09.030
TNO identifier
240601
ISSN
0021-9797
Source
Journal of Colloid and Interface Science, 317 (1), 137-147
Document type
article