文档介绍：PHYSICAL STATE OF INGREDIENTS IN FOOD SYSTEMS
Food Dispersions
1. True solution
2. Colloidal dispersion
3. Emulsion
4. Foam
5. Gel
 
Dispersions
1. Continuous phase
2. Dispersed phase
May be solid, liquid, or gas.
True Solution
The dispersion of particle < 1 nm in liquid.
Examples: sugar, lactose, minerals, and vitamins.
 
Colloidal Dispersion (SOL)
Dispersion of particle sizes between 10-100 nm in liquid.
Common colloids: dispersion of proteins, large molecular salts.
 
Example: milk.
Emulsions
Liquid/liquid systems of 2 immiscible substances are called emulsion. Substances or particle size = 10-100 microns.
Examples: butter (w/o), margarine (w/o), mayonnaise (o/w), salad dressing (o/w), milk (o/w), cream (o/w), and chip-dip (o/w).
Water
Oil
Oil
Oil
Oil
Oil
H O
H O
H O
H O
Oil/Water
Water/Oil
2
2
2
2
Oil
Oil
Oil
Oil
Oil
Oil
DESTABILIZATION OF THE DISPERSION
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Oil
Water
Water
Oil
Oil
Oil
Oil
Oil
Water
Oil
Aggregation
Oil separation
from water
EMULSIFIER
Oil
Water
Mayonnaise
Water
Oil
Margarine
Emulsifier
Hydrophobic
group
Hydrophilic
group
CHEMICAL STRUCTURE OF EMULSIFIERS
CH
3
CH
3
CH
3
CH
2
O C (CH
2
)
16
CH
3
O
O
N CH
2
CH
2
O P O CH
2
CH O C (CH
2
)
14
CH
3
O
O
CH
2
O C (CH
2
)
16
CH
3
HO CH
HO CH
2
O
CH
2
O C (CH
2
)
16
CH
3
CH O C (CH
2
)
16
CH
3
HO CH
2
O
O
Phospholipids (Lecithin)
Hydrophobic
(
fat-soluble)
Hydrophilic (water-soluble)
Mono-
Glycerides (mono-
stearate)
Hydrophobic
Hydrophilic
Di-glycerides (
di-stearate)
Hydrophobic
Hydrophilic
-
+
O
C CH CH
2
O C (CH
2
)
16
CH
3
C CH
C
H
2
H
O
OH
OH
H
HO
O
OH
O
H
2
O
C CH CH
2
O C (CH
2
)
16
CH
3
C CH
C
O CH
2
CH
2
O CH
2
CH
2
OH
CH
2
CH
2
O CH
2
CH
2
OH
Span 60 (sorbitan mono-stearate)
Hydrophobic
Hydrophilic
Tween 60 (polyox