It’s the beginning of the year and as we all head back to school, we get to look forward to setting up our rooms and unpacking science orders for the year. Even if you only have a small budget at your school, chances are, you’ve had to order some basics for the classroom, such as latex gloves, glassware, thermometers, and school supplies. All of these things are often shipped in boxes with packaging material, namely the packing peanut.
Some of these packing materials are made with starch. The plant material is biodegradable! These packing peanuts dissolve in water and in time will complete degrade.
Packing peanuts are edible, but since you aren’t sure how they are stored, it is not safe to eat them. (I have given the packing peanuts to rodents and crickets as food, though).
Experiments with Biodegradable Packing Peanuts
Here are some experiment suggestions that are suited for middle and high school, most only take a class period (or less).
Experiment 1: What type of liquid will the peanuts dissolve the fastest in? Will tearing up the peanut make it dissolve faster in water?
For this experiment, you will need to provide beakers with various forms of liquids, such as salt water, vinegar, cold water, warm water, white soda, detergent…etc.
Tearing up the peanut increases the surface area, you can also include some measurements on the surface area, mass and volume of the peanut.
Experiment 2: What is the mass of a packing peanut? Does the mass change if you crush the peanut?
You’ll need a balance or scale for this one. You can compact a packing peanut and make it very small, but it won’t change the mass. You’d be amazed at how many students believe that if you crush it into a small, dense mass then it will weigh more. As an extension, see how many packing peanuts you can squeeze into a jar or beaker.
Experiment 3: Packing Peanuts and Indicators
Iodine is an indicator for starch. It will change from an orange to a blue/black color when it comes into contact with starch. Test a packing peanut. Does it contain starch?
Dissolve a packing peanut in water. Does it still contain starch? Dissolve a packing peanut in water within a test tube and then add saliva by carefully spitting into the tube. Let it sit overnight.
Saliva contains an enzyme that breaks down starch into sugar. Separate your mixture (after it has sat overnight). Use iodine to test part of your mixture for starch. Use a glucose test strip to test the other half for sugar.