Interfacial activity and interfacial shear rheology of native ß-lactoglobulin monomers and their heat-induced fibers

Supporting Information

Interfacial activity and interfacial shear rheology of native ȕ -lactoglobulin monomers and their heat-induced fibers

Jin-Mi Jung¹, Deniz Zeynel Gunes² and Raffaele Mezzenga³*

1Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Ch.

Musée 3, CH-1700, Fribourg, Switzerland, ²Department of Food Science and Technology, Nestlé Research Center, Vers-chez-les-Blanc, Lausanne 26, CH-1000, Switzerland, ³ETH Zurich, Food & Soft Materials Science, Institute of Food, Nutrition & Health, LFO23, Schmelzbergstrasse 9, 8092 Zurich, Switzerland.

* to whom correspondence should be addressed: [email protected]

Determination of physical modifications of unconverted ȕ -lactoglobulin monomers after a heat treatment of 90°C and 5 hours by HPLC

1. HPLC-C18

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DAD1 A, Sig=214,4 Ref=off (G:\G15\HPC...ONATOL\RDLS100188\2010\C18 160210 2010-02-17 14-26-21\051-4501.D) DAD1 A, Sig=214,4 Ref=off (G:\G15\HPC...ONATOL\RDLS100188\2010\C18 160210 2010-02-17 14-26-21\052-4601.D)

71.027 72.222 73.442 74.477 77.675

Figure S1. C18-Chromatogram of the solution of native ȕ-lactoglobulin (2% wt, pH 2) (blue) and the filtrate of the heat-treated solution (90°C, 5h), obtained from ultra filtration through a 30kDa membrane (red).

2. HPLC-SEC

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DAD1 A, Sig=214,4 Ref=off (G:\G15\HPC...ONATOL\RDLS100188\2010\SEC 210210 2010-02-23 10-57-21\051-6801.D)

12.135 12.910 Area: 10749.5

15.646

Area: 22 474.2

16.234

Area: 105250

17.881

Area: 4298.55

18.869 20.650 21.741 24.049 24.744 26.575

Figure S2. HPLC-SEC chromatogram of the solution of native ȕ-lactoglobulin (2% wt, pH2).

Table S1. Corresponding elution times and areas for the peaks of Figure S1

# Time Area Area %

1 12.135 5409.2 3.356

2 12.91 2816.4 1.748

3 15.646 10749.5 6.67

4 16.234 22474.2 13.945 5 17.881 105249.5 65.308

6 18.869 4298.5 2.667

7 20.65 2711.5 1.683

8 21.741 3111.4 1.931

9 24.049 665.8 0.413

10 24.744 2190.6 1.359

11 26.575 1483 0.92

In Red : ȕ-lactoglobulin

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DAD1 A, Sig=214,4 Ref=off (G:\G15\HPC...ONATOL\RDLS100188\2010\SEC 210210 2010-02-23 10-57-21\052-6901.D)

Area: 825.98 17.476 Area: 864.

307

17.859

Area: 2562.

35 18.983 Area: 2623.79

19.485

Area: 5463.

20.400 41

Area: 3714.

2

21.185

Area: 3218.

34 21.779 Area: 5606.

98

22.565

Area: 2265.

33

23.288

Figure S3. HPLC-SEC chromatogram of the filtrate of the solution of heat treated ȕ- lactoglobulin (2%, pH2, 90°C, 5h) obtained from ultra filtration through a 30kDa membrane.

Table S2. Corresponding elution times and areas for the peaks of Figure S3

# Time Area Area %

1 17.476 826 3.043

2 17.859 864.3 3.184

3 18.983 2562.4 9.44

4 19.485 2623.8 9.666

5 20.4 5463.4 20.127

6 21.185 3714.2 13.683 7 21.779 3218.3 11.856

8 22.565 5607 20.656

9 23.288 2265.3 8.345

In Red : ȕ-lactoglobulin