- Water (55-64%)
- Milk Fat (10-20%)
- Sugar
- Other Chemicals
- Emulsifiers
- Stabilizers
The Chemistry
of Ice Cream
The Creation!
Ingredients
The Product!
Polysorbate 80
O
H
2
- Polyoxyethylene (20) sorbitan monooleate
- C H O
- Bent and tetrahedral portions
- Both polar and nonpolar ends (emulsifier)
Mix
Freeze
&
How do you mix
what shouldn't mix?
Emulsify
Stabilize
- Air, water, and fat are immiscible
- Xanthan Gum forms polymers
- Polymers are so big that the mixture cannot separate
- Stabilizers get in the way
IT'S A COLLOID!
It's All 3 Phases!
- Water is polar and fat is not
- Polysorbate 80 has a polar end and a nonpolar end
- Nonpolar end attracts fat
- Polar end attracts water
- This prevents separation
- Egg yolks can do this too.
Triglycerides
Why does it matter?!
- Freeze Speed
- Freeze Temperature
- CH2ORCHORCH2OR
- R is an acid in the form CO(CH2)2nCH3
- Many tetrahedrals
- Non-polar
- Freeze speed affects crystal size
- Big crystals make coarse ice cream
- Small crystals make smooth ice cream
- Quick freezing=small crystals
- Slow freezing=big crystals
- Fat+water+air mixture?
- Emulsification
- Stabilization
- Flavoring
Flavoring is hard!
- Gaseous air gives ice cream its softness
- Liquid water makes up most of it
- Solid ice (and toppings!) gives it its texture
- The flavoring needs to mix thoroughly
- Emulsifiers help mix flavors that shouldn't
- A combination of polar and non-polar ingredients allow for thorough flavoring
- Emulating chemicals can be used for any flavor
Sucrose
Ice Cream is Cold!
- C12H22O11
- Many bent OH groups connected to tetrahedrals
- Very polar
- Even though ice cream is mostly water, it freezes well below 0
- Colligative properties
- Many solute in the water including sugar, fat, and additives
- A Colloid is a mixture where small particles of one substance are in a medium of another
- An emulsion is a colloid of 2 liquids
- A foam is a colloid of a gas in a liquid
- In cream, fat, ice, and air are in a medium of water, which is normally immiscible
- Emulsifiers are used to keep colloids stable
Xanthan Gum
- C H O
- Monomer (forms polymers)
- Many different shapes
- Bent OH groups make it polar
- Size makes it a stabilizer
These are sometimes done simultaneously