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Gochev GG, Campbell RA, Schneck E, Zawala J, Warszynski P. Exploring proteins at soft interfaces and in thin liquid films - From classical methods to advanced applications of reflectometry. Adv Colloid Interface Sci 2024; 329:103187. [PMID: 38788307 DOI: 10.1016/j.cis.2024.103187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/12/2024] [Accepted: 05/12/2024] [Indexed: 05/26/2024]
Abstract
The history of the topic of proteins at soft interfaces dates back to the 19th century, and until the present day, it has continuously attracted great scientific interest. A multitude of experimental methods and theoretical approaches have been developed to serve the research progress in this large domain of colloid and interface science, including the area of soft colloids such as foams and emulsions. From classical methods like surface tension adsorption isotherms, surface pressure-area measurements for spread layers, and surface rheology probing the dynamics of adsorption, nowadays, advanced surface-sensitive techniques based on spectroscopy, microscopy, and the reflection of light, X-rays and neutrons at liquid/fluid interfaces offers important complementary sources of information. Apart from the fundamental characteristics of protein adsorption layers, i.e., surface tension and surface excess, the nanoscale structure of such layers and the interfacial protein conformations and morphologies are of pivotal importance for extending the depth of understanding on the topic. In this review article, we provide an extensive overview of the application of three methods, namely, ellipsometry, X-ray reflectometry and neutron reflectometry, for adsorption and structural studies on proteins at water/air and water/oil interfaces. The main attention is placed on the development of experimental approaches and on a discussion of the relevant achievements in terms of notable experimental results. We have attempted to cover the whole history of protein studies with these techniques, and thus, we believe the review should serve as a valuable reference to fuel ideas for a wide spectrum of researchers in different scientific fields where proteins at soft interface may be of relevance.
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Affiliation(s)
- Georgi G Gochev
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, 30239 Krakow, Poland; Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
| | - Richard A Campbell
- Division of Pharmacy and Optometry, University of Manchester, M13 9PT Manchester, UK
| | - Emanuel Schneck
- Physics Department, Technical University Darmstadt, 64289 Darmstadt, Germany
| | - Jan Zawala
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, 30239 Krakow, Poland
| | - Piotr Warszynski
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, 30239 Krakow, Poland
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2
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Hassan L, Xu C, Boehm M, Baier SK, Sharma V. Ultrathin Micellar Foam Films of Sodium Caseinate Protein Solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:6102-6112. [PMID: 37074870 DOI: 10.1021/acs.langmuir.3c00192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Sodium caseinates (NaCas), derived from milk proteins called caseins, are often added to food formulations as emulsifiers, foaming agents, and ingredients for producing dairy products. In this contribution, we contrast the drainage behavior of single foam films made with micellar NaCas solutions with well-established features of stratification observed for the micellar sodium dodecyl sulfate (SDS) foam films. In reflected light microscopy, the stratified SDS foam films display regions with distinct gray colors due to differences in interference intensity from coexisting thick-thin regions. Using IDIOM (interferometry digital imaging optical microscopy) protocols we pioneered for mapping nanotopography of foam films, we showed that drainage via stratification in SDS films proceeds by the expansion of flat domains that are thinner than surrounding by a concentration-dependent step-size, and nonflat features (nanoridges and mesas) form at the moving front. Furthermore, stratifying SDS foam films show stepwise thinning, such that the step-size and terminal film thickness decrease with concentration. Here we visualize the nanotopography in protein films with high spatiotemporal resolution using IDIOM protocols to address two long-standing questions. Do protein foam films formulated with NaCas undergo drainage via stratification? Are thickness transitions and variations in protein foam films determined by intermicellar interactions and supramolecular oscillatory disjoining pressure? In contrast with foam films containing micellar SDS, we find that micellar NaCas foam films display just one step, nonflat and noncircular domains that expand without forming nanoridges and a terminal thickness that increases with NaCas concentration. We infer that the differences in adsorbing and self-assembling unimers triumph over any similarities in the structure and interactions of their micelles.
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Affiliation(s)
- Lena Hassan
- Department of Chemical Engineering, University of Illinois Chicago, 929 West Taylor Street, Chicago, Illinois 60607, United States
| | - Chenxian Xu
- Department of Chemical Engineering, University of Illinois Chicago, 929 West Taylor Street, Chicago, Illinois 60607, United States
| | - Michael Boehm
- Motif Foodworks, 27 Drydock Avenue, Boston, Massachusetts 02210, United States
| | - Stefan K Baier
- Motif Foodworks, 27 Drydock Avenue, Boston, Massachusetts 02210, United States
- School of Chemical Engineering, The University of Queensland, Brisbane, 4072 Queensland, Australia
| | - Vivek Sharma
- Department of Chemical Engineering, University of Illinois Chicago, 929 West Taylor Street, Chicago, Illinois 60607, United States
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3
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Wierenga PA, Basheva ES, Delahaije RJBM. Variations in foam collapse and thin film stability with constant interfacial and bulk properties. Adv Colloid Interface Sci 2023; 312:102845. [PMID: 36709573 DOI: 10.1016/j.cis.2023.102845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 01/24/2023]
Abstract
The stability of foams is commonly linked to the interfacial properties of the proteins and other surfactants used. This study aimed to use these relationships to explain differences in foam stability observed among similar beer samples from different breweries. The foam stability was different for each sample (Nibem foam stability ranged from 206 to 300 s), but ranking was similar for all three foaming methods used, thus independent of the method, gas, etc. Differences in foam stability were dominated by differences in coalescence, as illustrated by the correlation with the stability of single bubbles and thin liquid films. The differences in coalescence stability could not be explained by the measured interfacial properties (e.g. surface pressure, adsorption rate, dilatational modulus and surface shear viscosity), or the bulk properties (concentration, pH, ionic strength, viscosity), since they were similar for all samples. The drainage rates and disjoining pressure isotherms measured in thin liquid films were also similar for all samples, further limiting the options to explain the differences in foam stability using known arguments. The differences in coalescence stability of the thin films was shown to depend on the liquid in between the adsorbed layers of the thin film, using a modified capillary cell to exchange this liquid (to a buffer, or one of the other samples). This illustrates the need to review our current understanding and to develop new methods both for experimental study and theoretical description, to better understand foam stability in the future.
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Affiliation(s)
- Peter Alexander Wierenga
- Laboratory of Food Chemistry, Wageningen UR, Bornse Weilanden 9, Wageningen 6708, WG, the Netherlands.
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4
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Rafe A, Selahbarzin S, Kulozik U, Hesarinejad MA. Dilatational rheology-property relationships of β-lactoglobulin /high methoxyl pectin mixtures in aqueous foams. Food Hydrocoll 2022. [DOI: 10.1016/j.foodhyd.2022.107683] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Rafe A, Glikman D, Rey NG, Haller N, Kulozik U, Braunschweig B. Structure-property relations of β-lactoglobulin/κ-carrageenan mixtures in aqueous foam. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128267] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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6
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On the foaming properties of plant proteins: Current status and future opportunities. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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7
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Ning B, Wang Y, Zhang M, Bai Y, Wang W, Wang G. Surface adsorption and foam performance of sodium perfluoroalkyl polyoxyethylene ether sulfate in ethanol-water mixed system. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116393] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Interfacial properties of milk proteins: A review. Adv Colloid Interface Sci 2021; 295:102347. [PMID: 33541692 DOI: 10.1016/j.cis.2020.102347] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/14/2020] [Accepted: 12/14/2020] [Indexed: 12/22/2022]
Abstract
The interfacial properties of dairy proteins are of great interest to the food industry. Food manufacturing involves various environmental conditions and multiple processes that significantly alter the structure and colloidal stability of food materials. The effects of concentration, pH, heat treatment, addition of salts etc., have considerable influence on the surface activity of proteins and the mechanical properties of the interfacial protein films. Studies to date have established some understanding of the links between environmental and processing related parameters and their impacts on interfacial behavior. Improvement in knowledge may allow better design of interfacial protein structures for different food applications. This review examines the effects of environmental and processing conditions on the interfacial properties of dairy proteins with emphasis on interfacial tension dynamics, dilatational and surface shear rheological properties. The most commonly used surface analytical techniques along with relevant methods are also addressed.
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Janssen F, Wouters AG, Chatzigiannakis E, Delcour JA, Vermant J. Thin film drainage dynamics of wheat and rye dough liquors and oat batter liquor. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2021.106624] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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10
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Dan A, Agnihotri P, Bochenek S, Richtering W. Adsorption dynamics of thermoresponsive microgels with incorporated short oligo(ethylene glycol) chains at the oil-water interface. SOFT MATTER 2021; 17:6127-6139. [PMID: 34076021 DOI: 10.1039/d1sm00146a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Herein, we report a systematic study of the adsorption behaviour of short oligo(ethylene glycol) (OEG) chains incorporated into poly(N-isopropylaccrylamide) (PNIPAM) microgels at the dodecane-water interface as a function of the microgel concentration at two different temperatures: 298 and 313 K. The dynamic interfacial tension of the interface for the adsorption of these functional microgels is measured by means of a pendent drop method. We find that similar to pure PNIPAM microgels, the functionalized microgels initially get transported from the bulk to the interface, where they undergo the deformability dependent spreading process, and thus leading to a reduction of interfacial tension. However, the OEG chains significantly influence the dynamic processes of the microgels at the interface, enabling precise control over the interfacial activity. A tuneability of adsorption behaviour that is interpreted in terms of the diversity of structural and morphological features of the microgels, can be achieved by changing the temperature and/or the OEG chain length of the comonomer. While the temperature induced phase transition generally slows down the adsorption kinetics of the microgels, increasing the temperature from 298 to 313 K allows faster reduction of interfacial tension for the adsorption of the microgels with long OEG chains among the studied comonomers, making them a unique interfacially active functional material. Overall, incorporation of OEG chains allows tailoring the interfacial activity of microgels, thereby paving the way for the use of these microgels to act as effective Pickering emulsion stabilizers in a range of applications.
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Affiliation(s)
- Abhijit Dan
- Department of Chemistry and Centre for Advanced Studies in Chemistry, Panjab University - Chandigarh, Sector 14, Chandigarh 160014, India.
| | - Priyanshi Agnihotri
- Department of Chemistry and Centre for Advanced Studies in Chemistry, Panjab University - Chandigarh, Sector 14, Chandigarh 160014, India.
| | - Steffen Bochenek
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Walter Richtering
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
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11
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β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 5. Adsorption Isotherm and Equation of State Revisited, Impact of pH. COLLOIDS AND INTERFACES 2021. [DOI: 10.3390/colloids5010014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The theoretical description of the adsorption of proteins at liquid/fluid interfaces suffers from the inapplicability of classical formalisms, which soundly calls for the development of more complicated adsorption models. A Frumkin-type thermodynamic 2-d solution model that accounts for nonidealities of interface enthalpy and entropy was proposed about two decades ago and has been continuously developed in the course of comparisons with experimental data. In a previous paper we investigated the adsorption of the globular protein β-lactoglobulin at the water/air interface and used such a model to analyze the experimental isotherms of the surface pressure, Π(c), and the frequency-, f-, dependent surface dilational viscoelasticity modulus, E(c)f, in a wide range of protein concentrations, c, and at pH 7. However, the best fit between theory and experiment proposed in that paper appeared incompatible with new data on the surface excess, Γ, obtained from direct measurements with neutron reflectometry. Therefore, in this work, the same model is simultaneously applied to a larger set of experimental dependences, e.g., Π(c), Γ(c), E(Π)f, etc., with E-values measured strictly in the linear viscoelasticity regime. Despite this ambitious complication, a best global fit was elaborated using a single set of parameter values, which well describes all experimental dependencies, thus corroborating the validity of the chosen thermodynamic model. Furthermore, we applied the model in the same manner to experimental results obtained at pH 3 and pH 5 in order to explain the well-pronounced effect of pH on the interfacial behavior of β-lactoglobulin. The results revealed that the propensity of β-lactoglobulin globules to unfold upon adsorption and stretch at the interface decreases in the order pH 3 > pH 7 > pH 5, i.e., with decreasing protein net charge. Finally, we discuss advantages and limitations in the current state of the model.
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12
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Braun L, Kühnhammer M, von Klitzing R. Stability of aqueous foam films and foams containing polymers: Discrepancies between different length scales. Curr Opin Colloid Interface Sci 2020. [DOI: 10.1016/j.cocis.2020.08.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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13
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Dachmann E, Nobis V, Kulozik U, Dombrowski J. Surface and foaming properties of potato proteins: Impact of protein concentration, pH value and ionic strength. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2020.105981] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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14
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β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 4. Impact on the Stability of Foam Films and Foams. MINERALS 2020. [DOI: 10.3390/min10070636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
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.
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15
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Gochev GG, Scoppola E, Campbell RA, Noskov BA, Miller R, Schneck E. β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 3. Neutron Reflectometry Study on the Effect of pH. J Phys Chem B 2019; 123:10877-10889. [PMID: 31725291 DOI: 10.1021/acs.jpcb.9b07733] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Several characteristics of β-lactoglobulin (BLG) layers adsorbed at the air/water interface exhibit a strong pH dependence, but our knowledge on the underlying structure-property relations is still fragmental. Here, we therefore extend our recent studies by neutron reflectometry (NR) and provide a comprehensive overview through direct measurements of the surface excess Γ and the layers' molecular structure. This enables comparison with available literature data to draw general conclusions. The NR experiments were performed at various pH values and within a wide range of protein concentrations, CBLG. Adsorption kinetics measurements in air-contrast-matched-water and over a narrow Qz range enabled direct quantification of the dynamic surface excess Γ(t) and are found to be consistent with ellipsometry data. Near the isoelectric point, pI, the rates of adsorption and Γ are maximal but only at sufficiently high CBLG. NR data collected over a wider Qz range and in two aqueous isotopic contrasts revealed the structure of adsorbed BLG layers at a steady state close to equilibrium. Independent of the pH, BLG was found to form dense monolayers with average thicknesses of 1.1 nm, suggesting flattening of the BLG globules upon adsorption as compared with their bulk dimensions (≈3.5 nm). Near pI and at sufficiently high CBLG, a thick (≈5.5 nm) but looser secondary sublayer is additionally formed adjacent to the dense primary monolayer. The thickness of this sublayer can be interpreted in terms of disordered BLG dimers. The results obtained and notably the specific interfacial structuring of BLG near pI complement previous observations relating the impact of solution pH and CBLG on other interfacial characteristics such as surface pressure and surface dilational viscoelasticity modulus.
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Affiliation(s)
- Georgi G Gochev
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany.,Institute of Physical Chemistry , Bulgarian Academy of Sciences , 1113 Sofia , Bulgaria
| | - Ernesto Scoppola
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| | - Richard A Campbell
- Institut Laue-Langevin , 71 Avenue des Martyrs, CS20156 , 38042 Grenoble , France.,Division of Pharmacy and Optometry , University of Manchester , M13 9PT Manchester , U.K
| | - Boris A Noskov
- Institute of Chemistry , St. Petersburg State University , 198504 Saint-Petersburg , Russia
| | - Reinhard Miller
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| | - Emanuel Schneck
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
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16
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Ulaganathan V, Del Castillo L, Webber JL, Ho TT, Ferri JK, Krasowska M, Beattie DA. The influence of pH on the interfacial behaviour of Quillaja bark saponin at the air-solution interface. Colloids Surf B Biointerfaces 2019; 176:412-419. [DOI: 10.1016/j.colsurfb.2019.01.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 11/29/2018] [Accepted: 01/05/2019] [Indexed: 10/27/2022]
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17
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How foam stability against drainage is affected by conditions of prior whey protein powder storage and dry-heating: A multidimensional experimental approach. J FOOD ENG 2019. [DOI: 10.1016/j.jfoodeng.2018.08.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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18
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Salt-dependent interaction behavior of β-Lactoglobulin molecules in relation to their surface and foaming properties. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2018.09.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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19
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Richert ME, García Rey N, Braunschweig B. Charge-Controlled Surface Properties of Native and Fluorophore-Labeled Bovine Serum Albumin at the Air-Water Interface. J Phys Chem B 2018; 122:10377-10383. [PMID: 30339752 PMCID: PMC6245422 DOI: 10.1021/acs.jpcb.8b06481] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
![]()
Proteins
at interfaces are important for protein formulations and
in soft materials such as foam. Here, interfacial stability and physicochemical
properties are key elements, which drive macroscopic foam properties
through structure–property relations. Native and fluorescein
isothiocyanate-labeled bovine serum albumin (BSA) were used to modify
air–water interfaces as a function of pH. Characterizations
were performed with tensiometry and sum-frequency generation (SFG).
SFG spectra of O–H stretching vibrations reveal a phase reversal
and a pronounced minimum in O–H intensity at pH values of 5.3
and 4.7 for native and labeled BSA, respectively. This minimum is
attributed to the interfacial isoelectric point (IEP) and is accompanied
by a minimum in surface tension and negligible ζ-potentials
in the bulk. Interfacial proteins at pH values close to the IEP can
promote macroscopic foam stability and are predominately located in
the lamellae between individual gas bubbles as evidenced by confocal
fluorescence microscopy. Different from the classical stabilization
mechanisms, for example, via the electrostatic disjoining pressure,
we propose that the presence of more close-packed BSA, because of
negligible net charges, inside the foam lamellae is more effective
in reducing foam drainage as compared to a situation with strong repulsive
electrostatic interactions.
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Affiliation(s)
- Manuela E Richert
- Institute of Physical Chemistry , Westfälische Wilhelms-Universität Münster , Corrensstraße 28/30 , 48149 Münster , Germany
| | - Natalia García Rey
- Institute of Physical Chemistry , Westfälische Wilhelms-Universität Münster , Corrensstraße 28/30 , 48149 Münster , Germany.,Center for Soft Nanoscience , Westfälische Wilhelms-Universität Münster , Busso-Peus-Straße 10 , 48149 Münster , Germany
| | - Björn Braunschweig
- Institute of Physical Chemistry , Westfälische Wilhelms-Universität Münster , Corrensstraße 28/30 , 48149 Münster , Germany.,Center for Soft Nanoscience , Westfälische Wilhelms-Universität Münster , Busso-Peus-Straße 10 , 48149 Münster , Germany
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21
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Narsimhan G, Xiang N. Role of Proteins on Formation, Drainage, and Stability of Liquid Food Foams. Annu Rev Food Sci Technol 2017; 9:45-63. [PMID: 29272186 DOI: 10.1146/annurev-food-030216-030009] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Foam is a high-volume fraction dispersion of gas into a liquid or a solid. It is important to understand the effect of formulation on shelf life and texture of food foams. The objective of this review is to elucidate mechanisms of formation and stability of foams and relate them to the formulations. Emulsifiers are important in foam formation, whereas proteins are generally preferred to provide long-term stability. Syneresis in foams is a precursor to their collapse in many instances. Intermolecular forces, conformation, and flexibility of proteins play an important role in foam stabilization. An adsorbed protein layer at air/water interfaces imparts interfacial rheology that is necessary to improve the shelf life of foam products. Wettability and spreading of food particles at the interface can stabilize or destabilize foams, depending on their properties. More studies are needed to fully understand the complex interplay of various mechanisms of destabilization in a real-food formulation.
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Affiliation(s)
- Ganesan Narsimhan
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, Indiana 47907, USA;
| | - Ning Xiang
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, Indiana 47907, USA;
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22
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Agbo C, Jakpa W, Sarkodie B, Boakye A, Fu S. A Review on the Mechanism of Pigment Dispersion. J DISPER SCI TECHNOL 2017. [DOI: 10.1080/01932691.2017.1406367] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Christiana Agbo
- Key Laboratory of Eco-Textile, Jiangnan University, Ministry of Education, Wuxi, Jiangsu, China
| | - Wizi Jakpa
- Key Laboratory of Eco-Textile, Jiangnan University, Ministry of Education, Wuxi, Jiangsu, China
| | - Bismark Sarkodie
- Key Laboratory of Eco-Textile, Jiangnan University, Ministry of Education, Wuxi, Jiangsu, China
| | - Andrews Boakye
- Key Laboratory of Eco-Textile, Jiangnan University, Ministry of Education, Wuxi, Jiangsu, China
| | - Shaohai Fu
- Key Laboratory of Eco-Textile, Jiangnan University, Ministry of Education, Wuxi, Jiangsu, China
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23
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Qin B, Ma D, Li F, Li Y. Aqueous clay suspensions stabilized by alginate fluid gels for coal spontaneous combustion prevention and control. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:24657-24665. [PMID: 28913598 DOI: 10.1007/s11356-017-9982-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 08/21/2017] [Indexed: 06/07/2023]
Abstract
We have developed aqueous clay suspensions stabilized by alginate fluid gels (AFG) for coal spontaneous combustion prevention and control. Specially, this study aimed to characterize the effect of AFG on the microstructure, static and dynamic stability, and coal fire inhibition performances of the prepared AFG-stabilized clay suspensions. Compared with aqueous clay suspensions, the AFG-stabilized clay suspensions manifest high static and dynamic stability, which can be ascribed to the formation of a robust three-dimensional gel network by AFG. The coal acceleration oxidation experimental results show that the prepared AFG-stabilized clay suspensions can improve the coal thermal stability and effectively inhibit the coal spontaneous oxidation process by increasing crossing point temperature (CPT) and reducing CO emission. The prepared low-cost and nontoxic AFG-stabilized clay suspensions, exhibiting excellent coal fire extinguishing performances, indicate great application potentials in coal spontaneous combustion prevention and control.
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Affiliation(s)
- Botao Qin
- Faculty of Safety Engineering, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, People's Republic of China.
- State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, People's Republic of China.
| | - Dong Ma
- Faculty of Safety Engineering, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
- State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
| | - Fanglei Li
- Faculty of Safety Engineering, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
- State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
| | - Yong Li
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
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Production and characterization of stable foams with fine bubbles from solutions of hydrophobin HFBII and its mixtures with other proteins. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2016.06.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Dombrowski J, Gschwendtner M, Kulozik U. Evaluation of structural characteristics determining surface and foaming properties of β-lactoglobulin aggregates. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2016.12.045] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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26
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Dombrowski J, Johler F, Warncke M, Kulozik U. Correlation between bulk characteristics of aggregated β-lactoglobulin and its surface and foaming properties. Food Hydrocoll 2016. [DOI: 10.1016/j.foodhyd.2016.05.027] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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27
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Interfacial properties, thin film stability and foam stability of casein micelle dispersions. Colloids Surf B Biointerfaces 2016; 149:56-63. [PMID: 27721166 DOI: 10.1016/j.colsurfb.2016.10.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 11/20/2022]
Abstract
Foam stability of casein micelle dispersions (CMDs) strongly depends on aggregate size. To elucidate the underlying mechanism, the role of interfacial and thin film properties was investigated. CMDs were prepared at 4°C and 20°C, designated as CMD4°C and CMD20°C. At equal protein concentrations, foam stability of CMD4°C (with casein micelle aggregates) was markedly higher than CMD20°C (without aggregates). Although the elastic modulus of CMD4°C was twice as that of CMD20°C at 0.005Hz, the protein adsorbed amount was slightly higher for CMD20°C than for CMD4°C, which indicated a slight difference in interfacial composition of the air/water interface. Non-linear surface dilatational rheology showed minor differences between mechanical properties of air/water interfaces stabilized by two CMDs. These differences in interfacial properties could not explain the large difference in foam stability between two CMDs. Thin film analysis showed that films made with CMD20°C drained to a more homogeneous film compared to films stabilized by CMD4°C. Large casein micelle aggregates trapped in the thin film of CMD4°C made the film more heterogeneous. The rupture time of thin films was significantly longer for CMD4°C (>1h) than for CMD20°C (<600s) at equal protein concentration. After homogenization, which broke down the aggregates, the thin films of CMD4°C became much more homogeneous, and both the rupture time of thin films and foam stability decreased significantly. In conclusion, the increased stability of foam prepared with CMD4°C appears to be the result of entrapment of casein micelle aggregates in the liquid films of the foam.
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28
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Braunschweig B, Schulze-Zachau F, Nagel E, Engelhardt K, Stoyanov S, Gochev G, Khristov K, Mileva E, Exerowa D, Miller R, Peukert W. Specific effects of Ca(2+) ions and molecular structure of β-lactoglobulin interfacial layers that drive macroscopic foam stability. SOFT MATTER 2016; 12:5995-6004. [PMID: 27337699 PMCID: PMC5048339 DOI: 10.1039/c6sm00636a] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/12/2016] [Indexed: 06/01/2023]
Abstract
β-Lactoglobulin (BLG) adsorption layers at air-water interfaces were studied in situ with vibrational sum-frequency generation (SFG), tensiometry, surface dilatational rheology and ellipsometry as a function of bulk Ca(2+) concentration. The relation between the interfacial molecular structure of adsorbed BLG and the interactions with the supporting electrolyte is additionally addressed on higher length scales along the foam hierarchy - from the ubiquitous air-water interface through thin foam films to macroscopic foam. For concentrations <1 mM, a strong decrease in SFG intensity from O-H stretching bands and a slight increase in layer thickness and surface pressure are observed. A further increase in Ca(2+) concentrations above 1 mM causes an apparent change in the polarity of aromatic C-H stretching vibrations from interfacial BLG which we associate to a charge reversal at the interface. Foam film measurements show formation of common black films at Ca(2+) concentrations above 1 mM due to considerable decrease of the stabilizing electrostatic disjoining pressure. These observations also correlate with a minimum in macroscopic foam stability. For concentrations >30 mM Ca(2+), micrographs of foam films show clear signatures of aggregates which tend to increase the stability of foam films. Here, the interfacial layers have a higher surface dilatational elasticity. In fact, macroscopic foams formed from BLG dilutions with high Ca(2+) concentrations where aggregates and interfacial layers with higher elasticity are found, showed the highest stability with much smaller bubble sizes.
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Affiliation(s)
- Björn Braunschweig
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany. and Cluster of Excellence Engineering of Advanced Materials (EAM), Nägelsbachstr. 49b, 91052 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Paul-Gordan-Straße 6, 91052 Erlangen, Germany and Interdisciplinary Center of Functional Particle Systems, Haberstraße 9a, 91058 Erlangen, Germany
| | - Felix Schulze-Zachau
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany. and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Paul-Gordan-Straße 6, 91052 Erlangen, Germany and Interdisciplinary Center of Functional Particle Systems, Haberstraße 9a, 91058 Erlangen, Germany
| | - Eva Nagel
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany.
| | - Kathrin Engelhardt
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany.
| | - Stefan Stoyanov
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Georgi Gochev
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria and Max-Planck-Institute of Colloids and Interfaces, 14476 Golm/Potsdam, Germany
| | - Khr Khristov
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Elena Mileva
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Dotchi Exerowa
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Reinhard Miller
- Max-Planck-Institute of Colloids and Interfaces, 14476 Golm/Potsdam, Germany
| | - Wolfgang Peukert
- Institute of Particle Technology (LFG), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Cauerstraße 4, 91058 Erlangen, Germany. and Cluster of Excellence Engineering of Advanced Materials (EAM), Nägelsbachstr. 49b, 91052 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), Paul-Gordan-Straße 6, 91052 Erlangen, Germany and Interdisciplinary Center of Functional Particle Systems, Haberstraße 9a, 91058 Erlangen, Germany
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29
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Lech FJ, Delahaije RJ, Meinders MB, Gruppen H, Wierenga PA. Identification of critical concentrations determining foam ability and stability of β-lactoglobulin. Food Hydrocoll 2016. [DOI: 10.1016/j.foodhyd.2016.01.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Dombrowski J, Dechau J, Kulozik U. Multiscale approach to characterize bulk, surface and foaming behavior of casein micelles as a function of alkalinisation. Food Hydrocoll 2016. [DOI: 10.1016/j.foodhyd.2015.12.022] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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31
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Fainerman VB. In honour of the 65th birthday of Reinhard Miller. Adv Colloid Interface Sci 2015; 222:1-8. [PMID: 26111457 DOI: 10.1016/j.cis.2015.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Engelhardt K, Peukert W, Braunschweig B. Vibrational sum-frequency generation at protein modified air–water interfaces: Effects of molecular structure and surface charging. Curr Opin Colloid Interface Sci 2014. [DOI: 10.1016/j.cocis.2014.03.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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