Effect of polymer addition

Question 1

What is the effect of addition of polymers ?

1. Same charge
2. Effect of concentration
3. Opposite charge
4. Addition after emulsification; in another question!

Answer 1

1.Same charge (polysaccharide negative and negative protein):
• No attraction, no complex formation
• Polysaccharides are in continuous phase (viscosity increase, take space)
2.Effect of concentration:
• Low concentration: stable (less flocculation, less creaming)
• High concentration: depletion interaction ?? more flocculation creaming phase separation.
3. Opposite charge (polysaccharides negative and positive proteins):
• attraction, complex formation
• System depends on preparation method (polysaccharide addition before emulsification or after emulsification)

Question 2

Addition of polymers after emulsification?

Answer 2

• Low concentration: unstable (bridging flocculation, more creaming), able to attach to the oil droplets.
• Higher concentration: stable (less flocculation, steric repulsion), emulsions droplet can become completely covered by polysaccharides.
*Even higher concentration: unstable (depletion interaction)

Question 3

Effect of charge:

Answer 3

• When droplets are no charge, the emulsion is stabilized by steric repulsion. More creaming
• Lot of charge of the polysaccharides, stability may be higher because, repeal each other. Steric repulsion and electrostatic repulsion. More space needed less creaming.