Next Article in Journal
Influence of Titaniferous Phases on Tungsten Mineralizing Processes at the Giant Sisson Brook W-Mo Deposit, New Brunswick, Canada: Mineral-Chemical and Geochronological Assessment
Previous Article in Journal
Gold in Irish Coal: Palaeo-Concentration from Metalliferous Groundwaters
Previous Article in Special Issue
Experimental Procedure for the Determination of the Critical Coalescence Concentration (CCC) of Simple Frothers
Open AccessArticle

β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 4. Impact on the Stability of Foam Films and Foams

1
Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, 30239 Krakow, Poland
2
Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
3
Institute of Biomaterial Science, Helmholtz-Zentrum Geesthacht, 14513 Teltow-Seehof, Germany
4
Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
5
Nestlé Research Center, CH-1000 Lausanne 26, Switzerland
6
Chair of Food and Bioprocess Engineering, TU Munich, 85354 Freising, Germany
7
Department of Physics, TU Darmstadt, 64289 Darmstadt, Germany
8
Institute of Physical Chemistry and Center for Soft Nanoscience, WWU Münster, 48149 Münster, Germany
*
Author to whom correspondence should be addressed.
Minerals 2020, 10(7), 636; https://doi.org/10.3390/min10070636
Received: 5 June 2020 / Revised: 8 July 2020 / Accepted: 14 July 2020 / Published: 17 July 2020
(This article belongs to the Special Issue Surfactants at Interfaces and Thin Liquid Films)
The complexity and high sensitivity of proteins to environmental factors give rise to a multitude of variables, which affect the stabilization mechanisms in protein foams. Interfacial and foaming properties of proteins have been widely studied, but the reported unique effect of pH, which can be of great interest to applications, has been investigated to a lesser extent. In this paper, we focus on the impact of pH on the stability of black foam films and corresponding foams obtained from solutions of a model globular protein—the whey β-lactoglobulin (BLG). Foam stability was analyzed utilizing three characteristic parameters (deviation time, transition time and half-lifetime) for monitoring the foam decay, while foam film stability was measured in terms of the critical disjoining pressure of film rupture. We attempt to explain correlations between the macroscopic properties of a foam system and those of its major building blocks (foam films and interfaces), and thus, to identify structure-property relationships in foam. Good correlations were found between the stabilities of black foam films and foams, while relations to the properties of adsorption layers appeared to be intricate. That is because pH-dependent interfacial properties of proteins usually exhibit an extremum around the isoelectric point (pI), but the stability of BLG foam films increases with increasing pH (3–7), which is well reflected in the foam stability. We discuss the possible reasons behind these intriguingly different behaviors on the basis of pH-induced changes in the molecular properties of BLG, which seem to be determining the mechanism of film rupture at the critical disjoining pressure. View Full-Text
Keywords: β-lactoglobulin; pH effect; foam; foam film; adsorption layer; drainage; coalescence; disjoining pressure β-lactoglobulin; pH effect; foam; foam film; adsorption layer; drainage; coalescence; disjoining pressure
Show Figures

Graphical abstract

MDPI and ACS Style

Gochev, G.G.; Ulaganathan, V.; Retzlaff, I.; Gehin-Delval, C.; Gunes, D.Z.; Leser, M.; Kulozik, U.; Miller, R.; Braunschweig, B. β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 4. Impact on the Stability of Foam Films and Foams. Minerals 2020, 10, 636. https://doi.org/10.3390/min10070636

AMA Style

Gochev GG, Ulaganathan V, Retzlaff I, Gehin-Delval C, Gunes DZ, Leser M, Kulozik U, Miller R, Braunschweig B. β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 4. Impact on the Stability of Foam Films and Foams. Minerals. 2020; 10(7):636. https://doi.org/10.3390/min10070636

Chicago/Turabian Style

Gochev, Georgi G.; Ulaganathan, Vamseekrishna; Retzlaff, Inga; Gehin-Delval, Cécile; Gunes, Deniz Z.; Leser, Martin; Kulozik, Ulrich; Miller, Reinhard; Braunschweig, Björn. 2020. "β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 4. Impact on the Stability of Foam Films and Foams" Minerals 10, no. 7: 636. https://doi.org/10.3390/min10070636

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop