New Processes for New Products. Impact of protein modification designed functionalities as food ingredients

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1 New Processes for New Products Impact of protein modification designed functionalities as food ingredients E. Allen Foegeding Department of Food, Bioprocessing and Nutrition Sciences North Carolina State University USA

2 Molecular Function Interfacial properties *Foams and Emulsions Network formation *Gels and films Soluble particles (heat stability) *Beverages

3 Modifications Soluble aggregates ŁDenaturation and aggregation Hydrolysis Deamidation Glycosylation Add other polymers

4 Angel Food Cake Form Foam (200 ml) Ł10% protein Ł12% Sugar Blend in: Ł33 g cake flour Ł75.8 g powdered sugar Bake

5 Stability of the wet foam Egg white bubbles remains stable Whey protein isolate bubbles destabilize # Bubbles/ mm 2 Area %W 1 50%W 50%E 1 100% E 100%W 2 50%W 50%E E.A. Foegeding, unpublished data. Time Elapsed (min)

80 60 40 20 0 100%W 1 50%W 50%E 1 100% E 100%W 2 50%W 50%E 2 0 2.

6 Expansion of cakes during cooking (Pernell et al., 2002, J. Food Sci., 67, 2945) Normalized peak height (cm) % EWP 5% EWP p10% EWP 10% WPI 15% WPI r20% WPI Temperature ( o C) Time (min)

, 67, 2945) Normalized peak height (cm) 10 8 6 4 2 0 2% EWP

7 Problem in cake structure Loss of bubble stability during baking 100% Egg White 75% Egg White & 25% WPI

8 Properties of Foams FORMATION Ł Foamability Effectiveness of gas encapsulation (Wilde and Clark, 1996) PHYSICAL PROPERTIES Ł Air phase volume (overrun) and bubble size Ł Rheological Shear moduli and yield stress STABILITY Ł Drainage Ł Coalescence Ł Disproportionation

phase volume (overrun) and bubble size Ł Rheological Shear moduli

9 Yield Stress (s o ) -Vane Technique Height Diameter Yield Stress (σ o ) (bubble size, air phase volume, interfacial tension and/or rheology)

10 Egg White vs. Whey Protein Isolate (Pernell et al., 2000, Journal of Food Science, 65, 110) 200 Egg White Mean yield stress (Pa) WPI Whipping time (min)

11 Hydrolysis to improve foaming Davis et al., 2005, J. Colloid and Interface Science, 288, 412 Extensive hydrolysis with Alcalase Improved yield stress and did not decrease overrun Yield Stress (Pa) controls 90C/15min 75C/30min % Overrun Beta-lg Alcalase WPI 0 Beta-lg Alcalase WPI

yield stress and did not decrease overrun Yield Stress (Pa) 140 120 100 80 60 40 20

12 Does it work in a cake? Cake Volume (ml) % hydro 10% hydro 10% EWP 10% blg 10% WPI

13 What happened during baking? WPI batters destabilize during the entire process 25 o C 35 o C 45 o C 55 o C 100% WPI 75% EWP/ 25% WPI 100% EWP Egg white batters remain stable during the entire process

14 Lesson: Functionality is the entire process! Improved wet Foam functionality But did not improve Thermal stability Protein/sugar foam Blend in wheat starch and protein (flour) Angel Food Cake Heat to expand air cells, set the protein/starch network and remove moisture

stability Protein/sugar foam Blend in wheat starch and protein

15 Whey proteins in Beverages Stability *No visible phase separation Clarity *Clear like soft drinks Flavor *No off-flavors *Low astringency Nutrition & Health *No changes in biological properties Beverage ph Clear Stable Astringent Opaque Not stable Less astringent

astringency Nutrition & Health *No changes in biological properties 1

16 General Approach Inhibit denaturation or alter aggregation ŁAddition of charged polysaccharides (dextran sulfate) ŁAddition of β- or α s -casein to act as molecular chaperones

17 A G = increasing DS concentration ph 5.6 Dextran Sulfate (DS) A* B C D E* F* G* ph 5.8 A B C D E F G* 6% β-lactoglobulin ph 6.0 Heated at 85 C for 15 min * = Gel ph 6.2 A B C D E F G* Vardhanabhuti, B. and Foegeding, Unpublished data A B C D E F G*

18 Effect of dextran sulfate M w at ph OD G G G G G G DS 5k DS 10k DS 100k DS 500k DS:BLG weight ratio Vardhanabhuti, B. and Foegeding, Unpublished data

5 1 G G G G G G DS 5k DS 10k DS 100k DS 500k 0.

19 Effect of NaCl 2.0 Gel Gel Gel Gel Gel Gel Gel OD Gel Gel control NaCl (mm) Vardhanabhuti, B. and Foegeding, Unpublished data DS effect removed

20 Caseins as Molecular Chaperones: Previous investigations Study ph Temp. ( o C) Time (min) Whey components (%) * a-lac (0.2) b-lac (0.2) Caseins (%) Total protein (%) a s -casein (0.6) 1.0 * b-lac (0.5) a s -casein (0.5) 1.0 * Whey protein isolate (0.5) a s1 /b-casein (0.5) 1.0 *1 Bhattacharyya and Das, J. Biol. Chem. (1999), vol. 274, p *2 Morgan et al., J. Agric. and Food Chem. (2005), vol. 53, p *3 O Kennedy and Mounsey, J. Agric. and Food Chem. (2006), vol. 54, p TOO LOW!

0 85 10 Whey protein isolate (0.5) a s1 /b-casein (0.5) 1.0 *1 Bhattacharyya and Das, J. Biol. Chem. (1999), vol. 274, p.

21 b-lactoglobulin & b-casein (BCN) 25 o C 70 o C 75 o C 80 o C 85 o C 90 o C Unheated solutions (25 o C) were clear BCN decreased the turbidity of heated solutions, especially 2% BCN (total protein 8%) Heating at 90 o C produced clearer solutions than at 75 o C Constant 6% (w/v) BLG BCN (%) Yong et al, unpublished data

22 Effect of different caseins 1.60 Maximum linear region OD 400 nm OD 600 nm BLG only BCN1 BCN2 Crude BCN ACN Two lots of BCN produced identical turbidity profiles A crude BCN showed a systematic shift up a s -Casein inhibited turbidity development at 70 o C matched with other studies However, turbidity increased drastically at 75 o C (lost chaperone ability) and formed gel at 90 o C Constant 6% (w/v) BLG Temperature ( o C) Yong et al, unpublished data

23 Molar Mass (SEC-MALS) Cumulative Weight Fraction Molar Mass (g/mol) BLG 75 o C BLG 90 o C BLG-BCN 75 o C BLG-BCN 90 o C BLG-ACN 75 o C BLG-ACN 90 o C Molar mass distribution at 25 o C -Mean 3.0X10 4 Molar mass distribution at 75 o C -BLG-BCN : 4.5x x10 7 -BLG-ACN : 5.6x x10 7 -BLG only : 3.2x x10 9 Molar mass distribution at 90 o C -BLG-BCN : 4.6x x10 7 -BLG-ACN : 1.9x x10 8 -BLG only : 2.2x x10 8 Yong et al, unpublished data

24 Root Mean Square Radius Cumulative Weight Fraction R.M.S. Radius (nm) BLG 75 o C BLG 90 o C BLG-BCN 75 o C BLG-BCN 90 o C BLG-ACN 75 o C BLG-ACN 90 o C Radius distribution at 75 o C -BLG-BCN : BLG-ACN : BLG only : Radius distribution at 90 o C -BLG-BCN : BLG-ACN : BLG only : Radius of BLG at 75 o C slightly higher than 90 o C Yong et al, unpublished data

25 Conclusion β-casein and as-casein showed chaperone effects by altering aggregation of β- lactoglobulin at ph 6 (8% w/v total protein) β-casein was shown to be an effective approach to alter aggregation of β-lactoglobulin over a range of temperatures (70-90 o C) α s -casein lost its chaperone ability at temperatures 75 o C

26 Thanks to: *Dairy Management Inc. and the Southeast Dairy Foods Research Center for funding *DAVISCO Foods International for donating the proteins Protein Synthesis Units

27 From: Questions?

F. Morgan, J.-J. Maugas

Whey, the natural source for a broad range of food ingredients F. Morgan, J.-J. Maugas LACTALIS R&D Whey Skim milk Milk Casein production Cheese production Acid Rennet Fresh cheeses Soft cheeses Semi-hard