1. Fractionation/Separation of Dairy Proteins
Mark R. Etzel
University of Wisconsin

2. Specific milk proteins
“For food manufacturers, understanding the roles played
by specific milk proteins provides us with a selection of
marketable target groups. By increasing the content of
selected proteins in milk, we increase the efficiency
of separation and formulation while reducing cost.”
Joe O’Donnell, Dairy Foods, May, 2001, p. 6.

3. Properties of proteins in milk
Protein (kg/mol) g/L pI
-lactoglobulin
-lactalbumin
serum albumin
immunoglobulins
lactoferrin
lactoperoxidase
k-casein
b-casein
as-caseins /5.3

4. Cost of separation processes
lactose
WPI LF

5. Potential economic impact
Fractions Sales Price
LF $300/kg $0.03/L
GMP $70 $0.10
ALA $60 $0.07
BLG $20 $0.06
IgG $90 $0.06
$0.32
Mixture
WPI $10 $0.06
Value of whey proteins ($0.32/L) ≈ Skim milk ($0.34/L)

6. Whey protein value
$0.32/L
28¥109 L/yr whey (USA)

7. Beverages and dietary supplements
— Soft drinks = $20 billion/yr
— Dietary supplements = $9 billion/yr (20% growth)
— Specific milk proteins have special medical benefits and unique functional properties that address important social and technical need for these industries

8. Functional beverages
— Functional beverages = $5 billion/yr (15% growth)
— Consumers can increase their health without drastic lifestyle changes
— Fortify milk, milk-based, and non-dairy beverages with specific milk proteins?

9. -Lactalbumin and serotonin pathway
Clinical indications:
Depression, Fibromyalgia, Obesity,
Insomnia, and Chronic Headache

10. Boiling of -lactalbumin
blg
ala

11. Glycomacropeptide
— prevents adhesion of E. coli and viruses to human endothelial cells by flooding sialic acid receptors
rats fed E. coli all died, whereas rats fed GMP first and then E. coli all lived
— prevents binding of enterotoxins to receptors
— prevents binding of bacteria to teeth (toothpaste)

12. GMP & PKU — only known protein free of phenylalanine
— new baked goods, beverages, and pasta for families having children with PKU
— sells for 50 times the price of whey powder
— children and adults with PKU, for the first time in their lives, will be able to safely eat foods made with protein (GMP) that taste good and provide the nutrition they need to be healthy

13. Lactoferrin – inhibits bacterial colonization (ear infections)
1/3 of doctor visits (by 3 yr = 80% of children)
most common reason for oral antibiotics
breast-fed babies have fewer ear infections
— anti-cancer properties
— reduces colonization of E. coli on beef

14. Flow sheet Q C/T UV AT pH Pump A B Column separated whey P 8 µm H2O
CIP
EQ (10x)
LF (10x)
LP (10x)
NaOH (10x)

15. BioProcess chromatography column

16. BioProcess system controller

17. Whey refinery models pH pH
salt
salt
salt
Crude
whey
cation
exchanger
anion
exchanger
whey
permeate
LA
LG LF LP
GMP
— Using one process, by changing solutions, can make:
• WPI & GMP
• LA, LG, LF, LP & GMP
• WPI, LF, LP & GMP
• etc.

18. ALA, BLG, LP, LF & GMP (option 2)
SDS-PAGE of fractions
whey
effluent
ALA
BLG LF LP
ALA, BLG, LP, LF & GMP (option 2)
whey
effluent
WPI
WPI & GMP (option 1)

19. Mass balance S-column steps: 1.) Equilibrate 2.) Whey 3.) Wash 4.) ALA
5.) BLG, BSA, IgG
6.) LP
7.) LF
8.) 0.2 M NaOH
Protein
Whey
Recovery
ALA
1.2 g/L
92 %
BLG
3.2 94
BSA
0.4
100
IgG
0.3 LP
0.03 LF
0.07
GMP
1.4
Q-column steps:
1.) Equilibrate
2.) Effluent
3.) Wash
4.) GMP
Protein
Effluent
Recovery
GMP
1.4
100%

20. Milk refinery Skim Milk Serum Protein Fractions MFP Milk Separator MF
IEX
MFR
Cream
IEX
Casein
Fractions

21. Casein Fractionation 202 121 79 41 a (24.4) a (24.4) 31.6 b (24.0)
k (19.0)
k (19.0)
17.8
8.2
MFR
0.08 M
0.19 M
0.30 M

22. Conclusions – Specific milk proteins have profitable applications
in beverages, infant formula, medical foods, processed
foods, and dietary supplements
– More research is needed on specific milk proteins:
1.) understand health benefits
2.) technology for recovery
3.) fortify milk, milk-based, and non-dairy beverages
4.) new medical foods (e.g. PKU, antiviral, antibacterial)
“No other food was designed solely to deliver nutrition and health to mammals.”
Joe O’Donnell, Dairy Foods, May, 2001, p. 6.