Fine-stranded and particulate gels of β-lactoglobulin and whey protein at varying pH

1992 ◽  
Vol 5 (6) ◽  
pp. 523-539 ◽  
Author(s):  
Maud Langton ◽  
Anne-Marie Hermansson
Keyword(s):  
Whey Protein ◽  
Particulate Gels ◽  
Β Lactoglobulin

Ultrasonic generation of aerated gelatin gels stabilized by whey protein β-lactoglobulin

2011 ◽  
Vol 25 (5) ◽  
pp. 958-967 ◽  
Author(s):  
R.N. Zúñiga ◽  
U. Kulozik ◽  
J.M. Aguilera
Keyword(s):  
Whey Protein ◽  
Gelatin Gels ◽  
Β Lactoglobulin

scholarly journals Exploring the Use of a Modified High-Temperature, Short-Time Continuous Heat Exchanger with Extended Holding Time (HTST-EHT) for Thermal Inactivation of Trypsin Following Selective Enzymatic Hydrolysis of the β-Lactoglobulin Fraction in Whey Protein Isolate

Foods ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 367 ◽  
Author(s):  
Laura Sáez ◽  
Eoin Murphy ◽  
Richard J. FitzGerald ◽  
Phil Kelly
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Whey Protein ◽  
Protein Isolate ◽  
Holding Time ◽  
High Temperature Short Time ◽  
Incubation Periods ◽  
Short Time ◽  
Β Lactoglobulin ◽  
Hydrolysis Of

Tryptic hydrolysis of whey protein isolate under specific incubation conditions including a relatively high enzyme:substrate (E:S) ratio of 1:10 is known to preferentially hydrolyse β-lactoglobulin (β-LG), while retaining the other major whey protein fraction, i.e., α-lactalbumin (α-LA) mainly intact. An objective of the present work was to explore the effects of reducing E:S (1:10, 1:30, 1:50, 1:100) on the selective hydrolysis of β-LG by trypsin at pH 8.5 and 25 °C in a 5% (w/v) WPI solution during incubation periods ranging from 1 to 7 h. In addition, the use of a pilot-scale continuous high-temperature, short-time (HTST) heat exchanger with an extended holding time (EHT) of 5 min as a means of inactivating trypsin to terminate hydrolysis was compared with laboratory-based acidification to <pH 3 by the addition of HCl, and batch sample heating in a water bath at 85 °C. An E:S of 1:10 resulted in 100% and 30% of β-LG and α-LA hydrolysis, respectively, after 3 h, while an E:S reduction to 1:30 and 1:50 led >90% β-LG hydrolysis after respective incubation periods of 4 and 6 h, with <5% hydrolysis of α-LA in the case of 1:50. Continuous HTST-EHT treatment was shown to be an effective inactivation process allowing for the maintenance of substrate selectivity. However, HTST-EHT heating resulted in protein aggregation, which negatively impacts the downstream recovery of intact α-LA. An optimum E:S was determined to be 1:50, with an incubation time ranging from 3 h to 7 h leading to 90% β-LG hydrolysis and minimal degradation of α-LA. Alternative batch heating by means of a water bath to inactivate trypsin caused considerable digestion of α-LA, while acidification to <pH 3.0 restricted subsequent functional applications of the protein.

Study of the interactions between rosmarinic acid and bovine milk whey protein α-Lactalbumin, β-Lactoglobulin and Lactoferrin

2015 ◽  
Vol 77 ◽  
pp. 450-459 ◽  
Author(s):  
Vincenza Ferraro ◽  
Ana Raquel Madureira ◽  
Bruno Sarmento ◽  
Ana Gomes ◽  
Manuela E. Pintado
Keyword(s):  
Whey Protein ◽  
Rosmarinic Acid ◽  
Bovine Milk ◽  
Milk Whey ◽  
Β Lactoglobulin ◽  
Milk Whey Protein

scholarly journals Dairy-Inspired Coatings for Bone Implants from Whey Protein Isolate-Derived Self-Assembled Fibrils

2020 ◽  
Vol 21 (15) ◽  
pp. 5544
Author(s):  
Rebecca Rabe ◽  
Ute Hempel ◽  
Laurine Martocq ◽  
Julia K. Keppler ◽  
Jenny Aveyard ◽  
...  
Keyword(s):  
Whey Protein ◽  
Antimicrobial Properties ◽  
Whey Protein Isolate ◽  
Protein Isolate ◽  
Surrounding Tissue ◽  
Osteoblastic Cell ◽  
Bone Contact ◽  
Acidic Solutions ◽  
Main Component ◽  
Β Lactoglobulin

To improve the integration of a biomaterial with surrounding tissue, its surface properties may be modified by adsorption of biomacromolecules, e.g., fibrils. Whey protein isolate (WPI), a dairy industry by-product, supports osteoblastic cell growth. WPI’s main component, β-lactoglobulin, forms fibrils in acidic solutions. In this study, aiming to develop coatings for biomaterials for bone contact, substrates were coated with WPI fibrils obtained at pH 2 or 3.5. Importantly, WPI fibrils coatings withstood autoclave sterilization and appeared to promote spreading and differentiation of human bone marrow stromal cells (hBMSC). In the future, WPI fibrils coatings could facilitate immobilization of biomolecules with growth stimulating or antimicrobial properties.

Heat stability of milk: pH-dependent dissociation of micellar κ-casein on heating milk at ultra high temperatures

1985 ◽  
Vol 52 (4) ◽  
pp. 529-538 ◽  
Author(s):  
Harjinder Singh ◽  
Partick F. Fox
Keyword(s):  
Whey Protein ◽  
Whey Proteins ◽  
Heat Stability ◽  
Casein Micelle ◽  
Casein Micelles ◽  
Ph Profile ◽  
Ph Values ◽  
Maximum Stability ◽  
Β Lactoglobulin ◽  
Maximum Minimum

SUMMARYPreheating milk at 140 °C for 1 min at pH 6·6, 6·8, 7·0 or 7·2 shifted the heat coagulation time (HCT)/pH profile to acidic values without significantly affecting the maximum stability. Whey proteins (both β-lactoglobulin and α-lactalbumin) co-sedimented with the casein micelles after heating milk at pH < 6·9 and the whey protein-coated micelles, dispersed in milk ultrafiltrate, showed characteristic maxima–minima in their HCT/pH profile. Heating milk at higher pH values (> 6·9) resulted in the dissociation of whey proteins and κ-casein-rich protein from the micelles and the residual micelles were unstable, without a maximum–minimum in the HCT/pH profile. Preformed whey protein–casein micelle complexes formed by preheating (140 °C for 1 min) milk at pH 6·7 dissociated from the micelles on reheating (140 °C for 1 min) at pH > 6·9. The dissociation of micellar-κ-casein, perhaps complexed with whey proteins, may reduce the micellar zeta potential at pH ≃ 6·9 sufficiently to cause a minimum in the HCT/pH profile of milk.

Comparison of the ability to bind lipids of β-lactoglobulin and serum albumin of milk from ruminant and non-ruminant species

1993 ◽  
Vol 60 (1) ◽  
pp. 55-63 ◽  
Author(s):  
M. Dolores Pérez ◽  
Pilar Puyol ◽  
José Manuel Ena ◽  
Miguel Calvo
Keyword(s):  
Fatty Acids ◽  
Guinea Pig ◽  
Serum Albumin ◽  
Whey Protein ◽  
Whey Proteins ◽  
Gel Filtration ◽  
Ruminant Species ◽  
Β Lactoglobulin

SummaryThe interaction of sheep, horse, pig, human and guinea-pig whey proteins with fatty acids has been studied. Using gel filtration and autoradiography, it was found that sheep β-lactoglobulin and serum albumin from all species had the ability to bind fatty acids in vitro. Sheep β-lactoglobulin, isolated from milk, had ˜ 0·5 mol fatty acids bound per mol monomer protein, and albumin from sheep, horse and pig contained ˜ 4·5, 2·9 and 4·7 mol fatty acids/mol protein respectively. However, β-lactoglobulin from horse and pig milk had neither fatty acids physiologically bound nor the ability to bind them in vitro. Albumin was the only whey protein detected with bound fatty acids in these species as well as in human and guinea pig. This suggests that the ability of ruminant β-lactoglobulin to bind fatty acids was not shared by the same protein of non-ruminants.

Determination of tensile strength of gels prepared from fractionated whey proteins

1986 ◽  
Vol 53 (2) ◽  
pp. 285-292 ◽  
Author(s):  
Keith R. Langley ◽  
David Millard ◽  
E. William Evans
Keyword(s):  
Tensile Strength ◽  
Whey Protein ◽  
Power Law ◽  
Whey Proteins ◽  
Heat Setting ◽  
Protein Gels ◽  
Novel Method ◽  
Β Lactoglobulin

SUMMARYA novel method for measuring tensile strength of heat-setting gels is described and is applied to whey protein gels. Contributions made by β-lactoglobulin and α-lactalbumin individually to the tensile strength of the gel are calculated. The tensile strength can be found from power law equations related to concentration of α-lactalbumin and β-lactoglobulin in whey protein mixtures.

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