Viscous behaviour of whey protein concentrate dispersions

Rattray, W.; Jelen, P.

doi:10.1016/0958-6946(95)00018-x

Cited by 19 publications

(26 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This indicated an increase in unfolding and denaturation of globular proteins when the pH of WPC was altered. In general, unfolding of globular proteins is frequently accompanied by an increase in the hydrodynamic radii of protein molecules and greater molecular entanglements which contribute to an increase in the apparent viscosity of WP solutions (Rattray & Jelen, 1995). Our finding suggests that adjusting acidity (H + ) and alkalinity (OH À ) of WPs while heating and shearing during extrusion could induce the conformational structure alteration of proteins since their net charges have been manipulated.…”

Section: Apparent Viscositymentioning

confidence: 85%

“…At higher protein concentrations, it was likely that denatured proteins were packed closely together, promoting protein-protein interactions, greater protein molecular entanglements, and polymerization, all of which contributed to the viscosity increases (Rector, 1992). In addition, swelling caused by hydrogen bonds between amino acid groups and water, resulting in an increase in the molecular radii of protein molecules could considerably be involved in the viscosity increase as well (Clark, 1998;Rattray & Jelen, 1995;Schmidt, Packard, & Morris, 1984). Thus, stabilizing and strengthening characteristics shown in of TWPC dispersions were more pronounced as the amount of denatured proteins increased.…”

Section: Influence Of Protein Concentrationmentioning

confidence: 92%

“…Perhaps by thermal and mechanical energy provided by extrusion process, b-Lg could be more denatured and contributed to high apparent viscosity or gelation at low pH. Accordingly, Rattray and Jelen (1995) reported that thermal treatment of acidic WPC solutions (11% and 20%, w/v, protein) at pH values < 3.5 caused relatively strong gels due to protein denaturation and aggregation. A similar observation was also reported by Singer, Yamamoto, and Latella (1988).…”

Section: Apparent Viscositymentioning

confidence: 95%

“…It was also observed that at 20% (w/w) WP dispersion, TWPC produced at pH 2.89 yielded a highly homogeneous, smooth, and viscous dispersion texture. It is interesting to note that an increase in apparent viscosity of highly acid-treated TWPC is the evitable outcome of acid-induced protein denaturation (Rattray & Jelen, 1995). The denaturation of a-lacalbumin (a-La) and bovine serum albumin (BSA) at pH 3.5 or lower were documented (Bernal & Jelen, 1984;Boye, Kalab, Alli, & Ma, 2000).…”

Section: Apparent Viscositymentioning

confidence: 96%

See 3 more Smart Citations

Rheological characterizations of texturized whey protein concentrate-based powders produced by reactive supercritical fluid extrusion

Manoi

Rizvi

2008

Food Research International

View full text Add to dashboard Cite

Section: Apparent Viscositymentioning

confidence: 85%

Section: Influence Of Protein Concentrationmentioning

confidence: 92%

Section: Apparent Viscositymentioning

confidence: 95%

Section: Apparent Viscositymentioning

confidence: 96%

See 2 more Smart Citations

Rheological characterizations of texturized whey protein concentrate-based powders produced by reactive supercritical fluid extrusion

Manoi

Rizvi

2008

Food Research International

View full text Add to dashboard Cite

“…For example, an increase in whey protein concentration causes intermolecular interactions of the proteins to become entangled; this leads to increased viscosity (Rattray and Jelen, 1995). Denaturation of globular whey proteins exposes R groups capable of hydrogen bonding in solution along with aggregation of unfolded proteins, resulting in higher viscosity (Schmidt et al, 1984).…”

Section: Viscositymentioning

confidence: 99%

A Comparison of Analytical Methods for Quantifying Denatured Whey Proteins and Their Correlation to Solubility

Allen¹

View full text Add to dashboard Cite

A Comparison of Analytical Methods for Quantifying Denatured Whey Proteins and Their Correlation to SolubilityMichelle Doreen AllenProtein structure affects the bioactivity and functionality of whey protein ingredients in food systems. Bioactivity of whey proteins and their derivatives are highly dependent upon primary, secondary and tertiary structure. The degree of denaturation of whey proteins is an important factor for determining how whey protein ingredients will perform in a food system. Several analytical methods have been developed to quantify protein denaturation of whey proteins. The goal of this project was to use a variety of analytical methods to quantify whey protein denaturation and to evaluate the correlation of denaturation to the functionality of whey protein powders.The objective of the first series of experiments was to compare three different analytical methods to measure denaturation of whey proteins in liquid whey obtained by various methods of separation and with varying degrees of heat treatment. A split plot experimental design was used. Raw bovine milk was skimmed and liquid whey was separated from the skim milk at natural pH. Three separation methods: 1) centrifugation,2) membrane filtration and 3) enzyme coagulation, made up the first split plot. Each subplot of liquid whey was then divided into three split plots to receive heat treatment. Heat treatments were no heat, 76°C for fifteen seconds and 85°C for three minutes. Each of the resulting nine treatment combinations was analyzed by 1) polyacrylamide gel electrophoresis, 2) bicinchoninic acid-soluble protein assay and 3) fluorescence spectroscopy to determine the amount of denatured protein in the liquid whey.Fluorescence spectroscopy was found to be the most sensitive and reliable method v for detecting differences in structure due to denaturation, while native polyacrylamide gel electrophoresis was found to be the least sensitive method. The sample which received the centrifugal treatment of isolation with no heat was found to be the most undenatured in structure while the sample which received the enzyme treatment of isolation with high heat was found to be the most denatured in structure.The objective of the second series of experiments was to evaluate the effect of denaturation on whey protein solubility in dried whey protein powders. Solubility is one of the most important functional properties to consider when selecting a whey protein ingredient, especially for beverage systems. Processing parameters are often manipulated in efforts to improve solubility. The protein structures of whey are considered to have an effect on solubility. Specifically, the degree of denaturation of whey proteins is thought to play a role in solubility.In this experimental design, raw bovine milk was skimmed and pasteurized then enzyme-coagulated at natural pH to separate the whey. Liquid whey was then split into three aliquots and each received one of the following treatments: 1) mild heat/ freeze dry, 2) mild heat/spray dry and 3) high ...

show abstract

Characterization and structure of cold-extruded whey protein isolate: impact of ball milling

Yang

et al. 2018

Appl Nanosci

View full text Add to dashboard Cite

Viscous behaviour of whey protein concentrate dispersions

Cited by 19 publications

References 15 publications

Rheological characterizations of texturized whey protein concentrate-based powders produced by reactive supercritical fluid extrusion

Rheological characterizations of texturized whey protein concentrate-based powders produced by reactive supercritical fluid extrusion

A Comparison of Analytical Methods for Quantifying Denatured Whey Proteins and Their Correlation to Solubility

Characterization and structure of cold-extruded whey protein isolate: impact of ball milling

Contact Info

Product

Resources

About