By Sarah Davis

Casein is quite easy to make at home with a few household ingredients. Casein has many uses, such as edible thickeners, or even industrially as a surfactant in paint, dye and paper. It can also be used in simple plastics to make buttons, bags and jewelry. It is a protein derived from milk that can be purchased in powder or paste form. For home application, it is easiest to use in a paste form, which can then be added to food or molded to make a plastic figurine. In food, it can be used as a substitute for emulsified fat or cream.

Casein should be a smooth, firm, white paste with a malleable texture after being strained.

Step 1

If you are planning to make a plastic figurine, cover the mold or surface in aluminum foil smoothing out all wrinkles as you cover.

Step 2

Line the colander or strainer with a double layer of cheese cloth.

Step 3

Fully mix together 1 tablespoon of milk and 1 teaspoon of baking soda in the small bowl so that no lumps remain.

Step 4

Add the remaining milk and baking soda slurry to the pot and warm it on a stove on medium to low heat, stirring occasionally to ensure that it does not burn on the bottom.

Step 5

When the milk begins to simmer turn off the heat and add the vinegar while stirring. The mixture will thicken and become slightly lumpy.

Step 6

Pour this mixture into the cheese cloth-lined strainer over the sink. When all liquid has strained through the cheese cloth, pull up the sides and gently press out excess liquid.

Step 7

Form the solids remaining in the cheesecloth into a small disc or ball and place it on the wax paper.

Step 8

If making a plastic figurine, roll out the casein ball to fit your mold and allow to cure for about three days or until solid. If using as a food thickener, pinch off a small amount and whisk into the item to be thickened.

Step 9

Wrap any unused casein tightly in plastic wrap for up to four days before use. If air reaches the wrapped casein, it will solidify.