How to Make Kid Safe Glue From Milk
Casein glue is glue made from the protein in milk. It is a very simple and quick glue to make and because it comes from milk it is non-toxic, safe and fun for kids in projects and woodworking.
Tools And Supplies
Skim Milk - http://amzn.to/2G7OYpC
Vinegar - http://amzn.to/2FNHngs
Baking soda - http://amzn.to/2G9JCu9
Step 1. Separate the casein from the whey
Start by warming up two cups of milk in a saucepan. This should be brought to a temperature that is warm to the touch, but not hot enough to hurt your hand. Next, add two and a half to three tablespoons of vinegar and stir the mix. You are looking for the whey to turn almost clear and separate into large chunks of casein and liquid whey. The separation will happen very quickly, if you have been stirring for a while and it has not happened then just add a little more vinegar.
Step 2. Strain and deacidify
Once the whey and casein have been separated, you can strain them through a towel or cheesecloth. You can also clump together the casein in the mix and just pull it out of the saucepan and dump off the whey. Next, we need to add a tablespoon of baking soda. This will react with the vinegar to bring the pH down to something less acidic.
Step 3. Add water and storage
Next, add 3 to 4 tablespoons of water and warm it on the stove. The baking soda will create bubbles and you need to watch the pot so it doesn't suds up. Keep mixing the lump of casein until it becomes completely liquid in the water. At that point it is done and ready for use. You can use it straight out of the saucepan or you can store it in a jar for future use. When kept in the fridge it will last for several weeks, but on the shelf you might want to use it that day as it will start to smell if it sits around too long.
Step 4. Use
Casein glue can be used for crafts supplies or anywhere where paper craft glue would be normally used. Some even use it for woodworking and other larger crafts. Because it is made from milk it is completely safe to use in food-related crafts and other places where kids will be tempted to drink the glue.