Gelation of Whey Protein Isolate Aggregates in Mixtures ... · 37 nm 77 nm. Title: Présentation...
1
Gelation of Whey Protein Isolate Aggregates in Mixtures with Sodium Caseinate Introduction Whey protein isolate is derived from milk whey.Its main component is β-lactoglobulin. Heating solutions of WPI leads to formation of aggregates of different morphologies and sizes. The aggregates of WPI are known for their ability to form gels in the presence of Ca 2+ (cold gelation). Here we study the kinetics of the gelation process (1) and how mixing the aggregates with sodium caseinate influences their gelation properties and the structure of the gels (2). Results • The size of the WPI aggregates (37 nm or 77 nm) does not influence the gelation speed, nor the modulus of the gels. • Increasing the temperature increases the gelation rate, but not the gel stiffness. Gelation is an activated process with activation energy E a = 220 kJ/mol. • Increasing the number of calcium ions per protein (R) increases the gelation rate, but not the gel stiffness. • Increasing the protein concentration increases both the gelation rate and the gel stiffness. • The gel structure is independent of the Ca concentration, but the gels are more heterogeneous at lower protein concentrations. Anna Kharlamova*,Taco Nicolai*, Christophe Chassenieux Université du Maine, IMMM UMR CNRS 6283, Avenue O. Messiaen 72085 Le Mans cedex 9 France • The structure of the gels is not influenced by the addition of sodium caseinate. Aggregate size Ca 2+ per protein Protein concentration 1 2 Conclusions Bba association and the Regional council of Brittany and Pays de la Loire are acknowledged for funding this work through the interregional PROFIL project, carried out by the association ‘Pole Agronomique Ouest’. • The rate of gelation of whey protein aggregates increases with increasing Ca concentration and increasing temperature, but the gels have the same structure and stiffness. • The structure and stiffness vary with the aggregate concentration, but not their size. • Whey protein aggregates have interesting functional properties allowing their use as ‘clean label’ texturizing ingredients (thickeners and gelling agents). *[email protected], [email protected] 16 th Food Colloids Conference Wageningen, April 10 – 13, 2016 Temperature Master curve Pure WPI aggregates • Addition of sodium caseinate to WPI aggregates simply slows down their gelation, but does not influence the gel modulus. • Activation energy controlling the WPI gelation is not influenced by the addition of sodium caseinate. Mixtures with sodium caseinate • Mixing sodium caseinate and WPI aggregates allows control over the viscosity at constant protein concentration. 10 g/L WPI 20 g/L WPI 30 g/L WPI 40 g/L WPI Arrhenius plot 40 g/L WPI agg. (37 nm) R = 6 Time (s) 10 2 10 3 10 4 10 5 G' (Pa) 10 -1 10 0 10 1 10 2 10 3 0 sc 20 sc 40 sc 60 sc 37 nm aggregates R = 8 Time (s) 10 0 10 1 10 2 10 3 10 4 10 5 G' (Pa) 10 -1 10 0 10 1 10 2 10 3 10 4 20 g/L wpi 40 g/L wpi Time (s) 10 3 10 4 10 5 10 6 G' (Pa) 10 -1 10 0 10 1 10 2 10 3 60 o C 55 o C 50 o C 45 o C 40 o C 35 o C T -1 (10 -3 K -1 ) 2,9 3,0 3,1 3,2 3,3 3,4 Shift factor 10 -3 10 -2 10 -1 10 0 10 1 10 2 10 3 20 g/L wpi 37 nm R=8 20 g/L wpi 77 nm R=8 40 g/L wpi 37 nm R=4 40 g/L wpi 37 nm R=6 40 g/L wpi 37 nm R=8 40 g/L wpi 77 nm R=4 40 g/L wpi 77 nm R=8 E A = 220 kJ/mol 20 g/L WPI agg. (37 nm) R=6 T -1 (10 -3 K -1 ) 2,8 2,9 3,0 3,1 3,2 3,3 Shift factor 10 -3 10 -2 10 -1 10 0 10 1 10 2 10 3 0 sc 20 sc 40 sc 60 sc 40 µm 20 g/L WPI agg. + 20 g/L sodium caseinate + 60 g/L sodium caseinate 40 µm Gels with 20 g/L WPI aggregates (32 nm) and R=9 40 g/L WPI agg. (37 nm) Time (s) 10 0 10 1 10 2 10 3 10 4 10 5 10 6 G' (Pa) 10 -1 10 0 10 1 10 2 10 3 10 4 R=4 R=6 R=8 WPI agg. + SC, total protein 90 g/L % WPI agg. 0 20 40 60 80 100 Viscosity (Pa.s) 10 -3 10 -2 10 -1 10 0 pH 6.0 pH 6.3 pH 6.6 pH 6.9 20 o C 60 o C 40 g/L WPI agg. (37 nm) R=4 Time (s) 10 2 10 3 10 4 10 5 G' (Pa) 10 -1 10 0 10 1 10 2 10 3 20 g/L WPI agg. R=8 Time (s) 10 2 10 3 10 4 10 5 G' (Pa) 10 -1 10 0 10 1 10 2 37 nm 77 nm
Transcript of Gelation of Whey Protein Isolate Aggregates in Mixtures ... · 37 nm 77 nm. Title: Présentation...
Gelation of Whey Protein Isolate Aggregates in Mixtures with Sodium Caseinate
Introduction Whey protein isolate is derived from milk whey. Its main component is β-lactoglobulin. Heating solutions of WPI leads toformation of aggregates of different morphologies and sizes. The aggregates of WPI are known for their ability to formgels in the presence of Ca2+ (cold gelation).Here we study the kinetics of the gelation process (1) and how mixing the aggregates with sodium caseinate influencestheir gelation properties and the structure of the gels (2).
Results
• The size of the WPI aggregates (37 nm or 77 nm)does not influence the gelation speed, nor themodulus of the gels.
• Increasing the temperature increases the gelationrate, but not the gel stiffness. Gelation is anactivated process with activation energy Ea = 220kJ/mol.
• Increasing the number of calcium ions per protein(R) increases the gelation rate, but not the gelstiffness.
• Increasing the protein concentration increasesboth the gelation rate and the gel stiffness.
• The gel structure is independent of the Caconcentration, but the gels are moreheterogeneous at lower protein concentrations.
Anna Kharlamova*, Taco Nicolai*, Christophe ChassenieuxUniversité du Maine, IMMM UMR CNRS 6283, Avenue O. Messiaen 72085 Le Mans cedex 9 France
• The structure of the gels is not influencedby the addition of sodium caseinate.
Aggregate size Ca2+ per proteinProtein
concentration
1
2
Conclusions
Bba association and the Regional council of Brittany and Pays de la Loire are acknowledged for funding this work through the interregional PROFIL project, carried out by theassociation ‘Pole Agronomique Ouest’.
• The rate of gelation of whey protein aggregates increases with increasing Ca concentration and increasing temperature,but the gels have the same structure and stiffness.• The structure and stiffness vary with the aggregate concentration, but not their size.• Whey protein aggregates have interesting functional properties allowing their use as ‘clean label’ texturizing ingredients(thickeners and gelling agents).
*[email protected], [email protected]
16th
Food
Col
loid
s C
onfe
renc
eW
agen
inge
n, A
pril
10 –
13,
2016
Temperature Master curvePure WPI aggregates
• Addition of sodium caseinate to WPI aggregatessimply slows down their gelation, but does notinfluence the gel modulus.• Activation energy controlling the WPI gelation isnot influenced by the addition of sodium caseinate.
Mixtures with sodium caseinate
• Mixing sodium caseinateand WPI aggregatesallows control over theviscosity at constantprotein concentration.
10 g/L WPI 20 g/L WPI 30 g/L WPI 40 g/L WPI
Arrhenius plot
40 g/L WPI agg. (37 nm)R = 6
Time (s)102 103 104 105
G' (
Pa)
10-1
100
101
102
103
0 sc20 sc40 sc60 sc
37 nm aggregates R = 8
Time (s)100 101 102 103 104 105
G' (
Pa)
10-1
100
101
102
103
104
20 g/L wpi40 g/L wpi
Time (s)103 104 105 106
G' (
Pa)
10-1
100
101
102
103
60 oC 55 oC50 oC45 oC40 oC35 oC
T-1 (10-3 K-1)2,9 3,0 3,1 3,2 3,3 3,4
Shift
fact
or
10-3
10-2
10-1
100
101
102
103
20 g/L wpi 37 nm R=820 g/L wpi 77 nm R=840 g/L wpi 37 nm R=440 g/L wpi 37 nm R=640 g/L wpi 37 nm R=840 g/L wpi 77 nm R=440 g/L wpi 77 nm R=8
EA = 220 kJ/mol
20 g/L WPI agg. (37 nm)R=6
T-1 (10-3 K-1)2,8 2,9 3,0 3,1 3,2 3,3
Shift
fact
or
10-3
10-2
10-1
100
101
102
1030 sc20 sc40 sc60 sc
40 µm
20 g/L WPI agg. + 20 g/L sodium caseinate
+ 60 g/L sodium caseinate
40 µm
Gels with 20 g/L WPI aggregates (32 nm) and R=9
40 g/L WPI agg. (37 nm)
Time (s)100 101 102 103 104 105 106
G' (
Pa)
10-1
100
101
102
103
104
R=4R=6R=8
WPI agg. + SC, total protein 90 g/L
% WPI agg.0 20 40 60 80 100
Visc
osity
(Pa.
s)
10-3
10-2
10-1
100pH 6.0pH 6.3pH 6.6pH 6.9
20 oC
60 oC
40 g/L WPI agg. (37 nm) R=4
Time (s)102 103 104 105
G' (
Pa)
10-1
100
101
102
103
20 g/L WPI agg. R=8
Time (s)102 103 104 105
G' (
Pa)
10-1
100
101
102
37 nm77 nm
![kLpSq;nm( 8 - Hindu · PDF filekLpSq;nm( 8 [KŒshyapa] 155 MAHARISHI UNIVERSITY OF MANAGEMENT VEDIC LITERATURE COLLECTION. sveR Tv; d ev; /UpyNt](https://static.fdocument.org/doc/165x107/5a8974d17f8b9a14748ea47f/klpsqnm-8-hindu-nm-8-koeshyapa-155-maharishi-university-of-management-vedic.jpg)
