Articles

    Operation Glue

    Kids, what do Little Miss Muffet's curds & whey have in common with glue? Just what is a curd, anyway? Curds are a milk protein called casein (a natural organic polymer) which actually has a lot of industrial uses. One of them is a key ingredient in Elmer's Glue-All. In Operation Glue, YOU can produce glue from milk using ordinary household products.

    Please note:  All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.

    Place 1/2 cup skim milk in a glass or jar. Add 1/8 cup vinegar and stir for a few minutes. Small lumps, which are curds, will form. Let them settle for a few minutes, then pour off as much liquid (the "whey") as possible. Filter the remainder through a cheesecloth until the curds are dry, and return them to the glass. Add about 1/2 teaspoon baking soda (for neutralization) to the curds, and mix. If the glue is too thick add a few drops of water. Now test your glue with a few pieces of paper.

    Notes: The process of separating curds from whey is very similar to the making of cottage cheese. Do not save the glue. Wash up with water. Whole milk will not work because the fat molecules precipitate with the casein and interfere with the glue structure, making it too weak.   

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    Kathleen Carrado Gregar, PhD, Argonne National Labs 
    [email protected]
    April 1992