Easy⏱ time30 min + dry$ cost3
Milk Plastic (Casein)
Curdle warm milk with vinegar and mould the solids into a hard, bone-like plastic.
Start building ↓
Result first
The build
Step 01
Heat the milk
Warm milk without boiling.
Step 02
Add vinegar
Stir in vinegar; white curds form.
Step 03
Strain & press
Collect curds and press out the liquid.
Step 04
Mould & dry
Shape it and let it harden for a day or two.
Working Principle
Acid makes the milk protein casein clump out of solution; pressed and dried, those protein chains set into a rigid natural plastic.
The science behind it
A closer look
Casein was an early plastic; the vinegar denatures and coagulates the protein into a mouldable solid.
Take it further
Variables to test
- 1 More vinegar — more plastic yield?
- 2 Compare whole vs skim milk for hardness.
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