Factors affecting membrane process

1. MEMBRANE
PROCESS
Presented By:
Gayathri Devi M K,
M.Tech Dairy Technology,
CFDT, TANUVAS, Chennai-52.
gdkrishnan97@gmail.com

2. ULTRAFILTRATION
Pressure-driven membrane filtration.
Larger components are rejected by the
membrane.
Retentate - Protein & fat
Permeate - Water, minerals, lactose,
NPN & water-soluble vitamins.
MWCO : 1–300 kDa
Pore size: ∼0.01 μm
Pressure of :<1000 kPa

3. THE RATE OF ULTRAFILTRATION OF MILK
 Retention of lactose may be up to 10%.
 25-fold whey concentrate = fourfold milk concentrate.

4. UF OF MILK
 Skim milk retentate powder
 Low lactose milk powder
 Skim milk based
concentrates
 Sweetened condensed milk
 Cheese making
 Cream
Milk Protein Standardization
Fermented Dairy Products
Ice – cream & Non – fat
dairy coffee whiteners

5. UF milk is currently being sold as a fluid
ingredient with higher protein and lower lactose
levels.
To produce a milk protein concentrate powder.
Include diafiltration steps for making yogurt and
ice cream.
UF milk for cheese milk fortification.
Nutrition:
Low- Carbo poduct.
Delivers high-quality protein.
Lactose-free or lactose reduced dairy products.
Dairy products that use UF milk have a fresh
flavor and an intact casein micelle.

6. Studies..,
Many studies revealed that thermal resistance of
some bacteria in UF milk retentates might be greater
than in unfiltered milk.
Adjustment of protein levels in milk up to 6·5 per
cent are reported to have no effect on the
organoleptic properties (Roenkilde Poulsen, 1978).
The use of UF concentrates in making sweetened
condensed milk has been found to avoid sandiness in
the texture (Serpa Alverez et al., 1979).
If milk is first concentrated by UF, it is possible to
prepare low-fat, high-protein whipping cream.

7. Studies..,
Camembert cheese can be made from UF milk
concentrates, with the advantage of a 20 per cent
increase in yield.
 The Alfa-Laval company has combined
ultrafiltration with its 'Camatic' process to make
Camembert cheese (Hansen, 1981).
The largest production using ultrafiltration is of
Feta cheese, mainly in Denmark for export.
UF milk is useful in formulating reduced- or
no-lactose dairy products. Recently, Atra et al. [2005]
proposed the integration of two-stage UF in milk.

8. Two-Stage UF in Milk

9. DAIRY INDUSTRY

10. Hood®
Carb
Dannon Light
‘n Fit®
AchieveOne
™
•Dairy beverage
•3g of lactose per 8-oz
serving
•Cultured dairy snack
• 3g carbohydrates
• 80% less sugar
•Coffee beverage with UF
milk protein concentrate.
COMMERCIAL PRODUCTS

11. Fouling
Irreversible deposition of solid
materials on the membrane
surface
Long term & irreversible
Concentration
Polarization
Unbalanced transport of dissolved
components between the bulk
phase and the membrane surface
Reversible & Short term
Effect of Milk Constituents on Operation of
Membrane Process

12. CONCENTRATION POLARIZATION
Protein–protein
Aggregation in
solution
Protein–
membrane
Pore
plugging
Hydrodynamic
conditions may
alleviate
fouling.
1 2 3

13. FOULING
Example Text : Get a modern PowerPoint
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Contents _ Graph
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Contents _ Graph
Attachment, removal/back
transport
Contents _ Graph
Slime formation
Microbial growth
Colloid deposition & Physical
compaction of the membrane
Deposition of macromolecules

14. Types
Particulate
Deposition of particulates,
biomass, and bacterial
particles aggregates.
Biofouling
Undesirable development of
microbial layers on membrane
surfaces
2
Organic
Accumulation of organic
material
(proteins, carbohydrate,
polysaccharides)
Inorganic
Accumulation of inorganic
Precipitates (as CaCO3,
CaSO4 & calcium phosphate)
1

15. Fouling (Huisman et al. )
Hydrophobic interactions
 Isoelectric point
 Hydrophobic
Aggregation of proteins
due to reduced electrostatic
repulsion.
Form a densely packed fouling
layer of low permeability.
Adsorption of more proteins

16. Mineral Precipitation
Adsorbed minerals may serve as salt
bridges
Promote calcium phosphate
precipitation or calcium–protein
Salts - Reduce the electrostatic
repulsion
Fat or lipid materials & calcium–
lipid complexes
Adopt cross flow filtration

17. Pulsatile flow
Baffles with pulsed flows with an oscillation frequency up to 2.5 Hz.
Backflushing
To pump filtrate back through the membrane into the feed channel .
Turbulence promoters
Tubular membranes placed concentric screw thread inserts.
Hydrodynamic Methods

18. Studies..,
Lee and Merson.. examined the structure of
protein deposits on 0.4 µm nucleopore
polycarbonate membranes by SEM. BSA and α-
lactoglobulin formed sheet-like deposits while
immunoglobulin G formed granules, which stacked
into layers creating a porous matrix.
Mohammadi et al. Results showed that a
combination of sodium dodecyl sulfate and sodium
hydroxide can be used as a cleaning material to
reach the optimum recovery of the polysulfone
membranes used in milk concentration industries.

19. REFERENCE
Chapter 10 Membrane fouling and cleaning-
Hongyu Li, UNSW Sydney,
https://www.researchgate.net/publication/2800
82517.
Handbook of Membrane Separations- Anil
K.Pabby.

20. THANK YOU
Email:gdkrishnan97@gmail.com