Where can you find gelatin?

Gelatin is a common ingredient in foods because it is so versatile. It can be used as a gelling agent (as in Jell-O), as a thickener, an emulsifier, and a stabilizer. You'll find it in a variety of foods, from yogurt to chewing gum. Here is a list of some other foods that commonly contain gelatin:

• gummy bears
• sour cream
• cream cheese
• cake icing and frosting
• marshmallows
• soups, sauces and gravies
• canned ham and chicken
• corned beef
• sausage

Gelatin is even used to make the coating for pills that makes them easier to swallow. It's also in cosmetics, lozenges, and ointments.

If you are using a special mold, you need to pour the
gelatin mix into the mold before you chill it. The finished
product will take on the shape of the container holding it.

When you buy a box of Jell-O (or another brand of gelatin) at the grocery store, you get a small packet of powdered gelatin with artificial flavorings and colors. At room temperature, the gelatin protein is in the form of a triple helix. This is a fairly ordered structure not unlike that of DNA. With DNA, two chains of nucleotides are twisted together in a spiral pattern. In the gelatin protein, there are three separate chains of amino acids (polypeptide chains) have lined up and twisted around each other, and the helix is held together by weak bonds that form between the amino acids that end up on the inside of the coiled structure.

To make a gelatin mold, you have to add boiling water to the powdered gelatin. You then stir the mixture for about 3 minutes until the gelatin dissolves completely.

What happens to gelatin when you add boiling water? The energy of the heated water is enough to break up the weak bonds holding the gelatin strands together. The helical structure falls apart, and you are left with free polypeptide chains floating about in solution.

The next step is to add cold water and stick the dissolved gelatin in the refrigerator to chill for several hours. When you cool down the mixture, the polypeptide chains begin to reassociate and reform the tight triple helix structure. However, the chilling process is slow, and the individual strands have been widely dispersed by mixing, so the helices aren't perfectly formed. In some places, there are gaps in the helix, and in others, there is just a tangled web of polypeptide chains. When the gelatin solution is chilled, water is trapped inside these gaps and pockets between chains. The protein net that is left after chilling gives the gelatin mold its shape, and the trapped water provides the characteristic Jell-O jiggle that makes it a popular food for kids to eat.

To learn more about Jell-O and related topics, check out the links on the next page.