EFFECT OF PROTEIN CONCENTRATION ON KINETICS OF WATER VAPOUR ADSORPTION BY COATINGS PREPARED ON THE BASIS OF WHEY PROTEIN ISOLATE

The secondary structure of proteins in unheated and heated whey protein isolate dispersions and the surface tension of the solutions were investigated at different pH. Heating protein solutions at 80°C results in an increase of unordered structure. Nevertheless, the difference between the contents of unordered structure in the unheated and heated samples increases with increasing pH of the solution. At low protein concentrations the surface tension decreased with increasing protein concentration to about 5 mg/ml. For the heated solution, a similar trend was observed in the decrease in the surface tension with increasing concentrations of protein. In both cases, the curves depicting the surface tension as a function of protein concentration could be fitted to the exponential function with a negative exponent, but with the heated solutions lower values of surface tension were observed. Studies on the surface tension of whey protein isolate solutions prove that the unfolding of whey proteins, revealed by changes in the secondary structure, causes a decrease in the surface tension.

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Kinetic model of water vapour adsorption by gluten-free starch

International Agrophysics ◽

10.1515/intag-2015-0006 ◽

2015 ◽

Vol 29 (1) ◽

pp. 115-119

Author(s):

Aneta Ocieczek ◽

Robert Kostek ◽

Millena Ruszkowska

Keyword(s):

Water Content ◽

Water Vapour ◽

Adsorption Process ◽

Starch Granules ◽

Gluten Free ◽

First Order ◽

Vapour Adsorption ◽

Water Vapour Adsorption ◽

Kinetics Of ◽

Over Time

Abstract This study evaluated the kinetics of water vapour adsorption on the surface of starch molecules derived from wheat. The aim of the study was to determine an equation that would allow estimation of water content in tested material in any timepoint of the adsorption process aimed at settling a balance with the environment. An adsorption isotherm of water vapour on starch granules was drawn. The parameters of the Guggenheim, Anderson, and De Boer equation were determined by characterizing the tested product and adsorption process. The equation of kinetics of water vapour adsorption on the surface of starch was determined based on the Guggenheim, Anderson, and De Boer model describing the state of equilibrium and on the model of a first-order linear inert element describing the changes in water content over time.

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Cold-Set Whey Protein Isolate Gels: The Influence of Aggregates Concentration on Viscoelastic Properties

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.1143 ◽

2011 ◽

Vol 312-315 ◽

pp. 1143-1148

Author(s):

M. Vázquez da Silva ◽

João M.P.Q. Delgado

Keyword(s):

Whey Protein ◽

Protein Concentration ◽

Room Temperature ◽

Young Modulus ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Holding Time ◽

Solution Viscosity ◽

Experimental Conditions ◽

Weak Gels

The physical and structural properties of cold-set whey protein isolate gels are largely influenced by the protein concentration and the denaturation conditions, namely temperature and holding time. In this work, we systematically varied the protein concentration, the temperature and holding time of denaturation in order to screen their impact on the resulting heat denatured whey protein isolate (HD-WPI) solution viscosity and gel elasticity. The gelation of the HD-WPI solutions was induced, at room temperature, through the addition of magnesium chloride. Based on the assumption that solution turbidity is associated with light scattered by protein aggregates, an aggregate concentration was computed for the HD-WPI solutions. For all experimental conditions, HD-WPI solution viscosities and gels Young modulus data fall, respectively, on two single curves when plotted against the computed aggregates concentration. Three concentration regimes corresponding to non gelling solutions, weak gels and strong gels could be identified. In this study was verified that cold-set gels produced upon addition of Mg2+ had a large spectrum of elastic properties.

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3D printed milk protein food simulant: Improving the printing performance of milk protein concentration by incorporating whey protein isolate

Innovative Food Science & Emerging Technologies ◽

10.1016/j.ifset.2018.07.018 ◽

2018 ◽

Vol 49 ◽

pp. 116-126 ◽

Cited By ~ 26

Author(s):

Yaowei Liu ◽

Dasong Liu ◽

Guanmian Wei ◽

Ying Ma ◽

Bhesh Bhandari ◽

...

Keyword(s):

Whey Protein ◽

Protein Concentration ◽

Milk Protein ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Protein Food ◽

Food Simulant ◽

3D Printed

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Kinetics of microstructure formation of high-pressure induced gel from a whey protein isolate

Journal of Physics Conference Series ◽

10.1088/1742-6596/215/1/012169 ◽

2010 ◽

Vol 215 ◽

pp. 012169 ◽

Cited By ~ 3

Author(s):

Jin-Song He ◽

Hongwei Yang ◽

Wanpeng Zhu ◽

Tai-Hua Mu

Keyword(s):

High Pressure ◽

Whey Protein ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Microstructure Formation ◽

Kinetics Of

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Development and Assessment of Duplex and Triplex Laminated Edible Films Using Whey Protein Isolate, Gelatin and Sodium Alginate

International Journal of Molecular Sciences ◽

10.3390/ijms21072486 ◽

2020 ◽

Vol 21 (7) ◽

pp. 2486 ◽

Cited By ~ 1

Author(s):

Andrey A. Tyuftin ◽

Lizhe Wang ◽

Mark A.E. Auty ◽

Joe P. Kerry

Keyword(s):

Sodium Alginate ◽

Whey Protein ◽

Water Vapour ◽

Corn Oil ◽

Barrier Properties ◽

Break Point ◽

Whey Protein Isolate ◽

Edible Films ◽

Protein Isolate ◽

Vapour Permeability

The objective of this study was to assess the ability of producing laminated edible films manufactured using the following proteins; gelatin (G), whey protein isolate (WPI) and polysaccharide sodium alginate (SA), and to evaluate their physical properties. Additionally, films’ preparation employing these ingredients was optimized through the addition of corn oil (O). Overall, 8-types of laminated films (G-SA, G-WPI, SA-WPI, SA-G-WPI, GO-SAO, GO-WPIO, SAO-WPIO and SAO-GO-WPIO) were developed in this study. The properties of the prepared films were characterized through the measurement of tensile strength (TS), elongation at break point (EB), puncture resistance (PR), tear strength (TT), water vapour permeability (WVP) and oxygen permeability (OP). The microstructure of cross-sections of laminated films was investigated by scanning electron microscopy (SEM). Mechanical properties of films were dramatically enhanced through the addition of film layers. GO-SAO laminate showed the best barrier properties to water vapour (22.6 ± 4.04 g mm/kPa d m2) and oxygen (18.2 ± 8.70 cm3 mm/kPa d m2). SAO-GO-WPIO laminate film was the strongest of all laminated films tested, having the highest TS of 55.77 MPa, PR of 41.36 N and TT of 27.32 N. SA-G-WPI film possessed the highest elasticity with an EB value of 17.4%.

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