Making Natural Plastic From Dairy Products

Polymerize Casein in Milk to Make a Polymer

Plastic Resin Pellets

MiguelMalo / Getty Images

Plastics are generally produced from petroleum, but they can come from other sources as well! All that is really required is the ability to join molecules containing carbon and hydrogen together, which you do whenever you curdle milk. This takes about 30 minutes.

What You Need

  • 1/2 C milk or heavy cream
  • vinegar or lemon juice
  • saucepan


  1. Pour 1/2 cup milk or heavy cream in a saucepan and heat to simmering over low to medium heat.
  2. Stir in a few spoonfuls of vinegar or lemon juice. Continue adding vinegar or lemon juice until the mixture starts to gel.
  3. Remove from heat and allow to cool.
  4. Rinse the rubbery curds with water. The curds are plastic! Play with your cool creation :-)

Useful Tips

  1. Adult supervision please - hot stove!
  2. The plastic is formed as a result of a chemical reaction between the casein in the dairy product and the acid (acetic in the vinegar, citric and ascorbic in the lemon juice).