Cooking is really an artistic variation of chemistry! Here's a fun and easy Christmas holiday project for the chemistry lab. Make these peppermint cream wafers for a seasonal project or demonstration.
Time Required: 30 minutes
- First, make sure all of the measuring utensils and glassware are clean and dry. If possible, use beakers that have never been used for more tradition chemistry experiments, since residues of chemicals can remain in the glass.
- Measure and mix the following chemicals in a 250-ml beaker: 1/4 cup or 2 tablespoons or 2 level medicine cups of sugar; 8 ml (1.5 tsp) milk; 10 ml (2 tsp) Karo syrup; 1/4 tsp or pea-sized amount of cream of tartar.
- Heat the mixture until its temperature reaches 200°F, stirring often.
- Once the temperature reaches 200°F, cover the beaker (with foil) and remove it from the heat for 2 minutes.
- Return the mixture to the heat. Heat and stir until the temperature reaches 240°F (soft-ball on a candy thermometer).
- Remove the mixure from heat and add one drop of peppermint oil and 1-2 drops of food coloring.
- Stir until the mixture is smooth, but not any longer than that or else the candy could harden in the beaker. Avoid stirring longer than 15-20 seconds.
- Pour coin-sized drops of the mixture onto a sheet of foil. Depending on the size of the drops, you will get 8-12 of them. Allow the candy to cool, then peel the drops off to enjoy your treat! Hot water is sufficient for clean-up.
- You can use wooden tongue depressors or metal spoons for stirring.
- Disposable plastic measuring cups, such as those used to dispense liquid medications, work well for measuring the ingredients for a lab of students.
- The mixture can be heated over a hotplate or a bunsen burner, with a ring stand and wire gauze pad. You could also use a stove.
- The texture of the finished product depends on the heating/cooling of the sugar mixture. You could get jellied candies or rock candy. It's a nice opportunity to discuss crystal structures.
What You Need
- sucrose (table sugar)
- concentrated liquid sucrose (or Karo syrup)
- potassium tartrate (cream of tartar)
- lactose (we will use milk)
- food coloring
- oil of peppermint
- 250 ml beaker or a saucepan
- candy thermometer or other metal-backed thermometer
- aluminum foil
- assorted labware or utensils for stirring, etc.