Food emulsion

A brief introduction to food emulsion.

1. 1"
FOOD EMULSIONS
Abd Karim Alias, 2013©
Prof. Abd Karim Alias
Universiti Sains Malaysia
Photo"courtesy"of"Tim"Sackton"on"Flickr""

2. 2"
! An emulsion consists of two
immiscible liquids (oil & water),
with one of the liquids dispersed
as small spherical droplets in the
other.
! In foods, the diameter of these
droplets usually falls somewhere
in the range 0.1 – 100 µm.
Food Emulsion
Abd Karim Alias, 2013©

3. 3"
! Two types of simple emulsion:
! Water-in-oil (w/o): margarine,
butter, spreads
! Oil-in-water (o/w): mayonnaise,
salad dressings, milk, beverages,
cream, soups, sauces
! The dispersed and/or continuous
phase of many food emulsions may
be partly crystalline, rather than
being completely liquid.
Food Emulsion
Abd Karim Alias, 2013©

4. 4"
! Emulsion formation requires the
dispersion of one phase into small
droplets ⇒ this results in a massive
increase in interfacial area between the
dispersed & continuous phase.
! Homogenization is the process by which
the dispersed phase is broken into small
droplets; high pressure homogenizers (10
– 100 MPa) are now very common.
Formation of Emulsion
Abd Karim Alias, 2013©

5. 5"
Formation of Emulsion
Abd Karim Alias, 2013©

6. 6"
Formation of Emulsion
"
Shear force
Abd Karim Alias, 2013©

7. 7"
Importance of Large Interfacial Area
For a fixed composition:
• Decrease size, increase number of
particles
• Increase area of interfacial contact
Increase area
Abd Karim Alias, 2013©

8. 8"
Formation of Emulsion
Abd Karim Alias, 2013©