Most kids don’t think about Thanksgiving and experiments as going together, but for us grownups, preparing a Thanksgiving dinner is all about experimenting. It’s in the kitchen where we discover how yeast works, what causes food to smell, how baking soda reacts with sour milk, and why biscuits sometimes rise and sometimes don’t. For teachers looking for some fun Thanksgiving themed experiments for the classroom, these are easy Thanksgiving food related experiments that you can do.
Extracting plastic from milk: It’s probably happened to all of us. We leave a small carton or thermos of milk in our locker, and weeks later, when we open up the carton, what’s inside has turned to stinky smelly chunks of goo. Those chunky bits of milk are the curds, also known as casein and this happens when the proteins in the milk solids separate from the milk fluids. Casein is a type of natural plastic, which are made of polymers. And polymers are very long chains of tiny molecules that look a little bit like tangled up Mardi Gras beads.
There’s a very easy method of extracting casein from milk that doesn’t involve leaving a thermos in your locker for a month. This experiment calls for a saucepan, wooden spoon, hot plate, 2 cups of milk, 2 TB vinegar, and something to strain the curds through (like a handkerchief):
1. Heat the milk til barely warm. Remove from heat
2. Stir in the vinegar.
3. Watch the curds form immediately.
4. Strain the milk through the handkerchief to catch the milk solids (the casein).
5. Shape the plastic into small dice.
6. Let dry overnight and examine the results.
The process of curdling can be sped up by using vinegar and warm temperatures. These two variables cause the casein to separate from the whey, leaving you and your students with a handful of natural plastic that can be shaped into jewelry or some other small item. You can read about the entire experiment here.
How preservatives work. Preservatives are something that is added to food to prevent it from spoiling. In the old days, salt and sugar were the only ways that food could be preserved. Much later, people discovered that vinegar also worked to stop spoilage. One fun experiment is to see exactly how preservatives work. Supplies needed include 3 pint canning jars (or clean jam jars), 1 chicken bouillon cube, 1 tp salt, and one teaspoon vinegar.
1. Mix the bouillon cube with one cup of hot water, stirring to dissolve.
2. Place equal amounts of the broth into the jars.
3. Label the jars with the words “vinegar”, “salt” and “control”.
4. Place vinegar in the jar marked vinegar.
5. Place the salt in the jar marked salt.
6. Set all 3 glasses in a warm place for several days. Have your students guess what the results might be.
Testing for starch: Thanksgiving meals are full of starch with all those yummy potatoes, rolls, corn, and stuffing which as we all know should be eaten in moderation.
Your students will quickly learn what foods contain starch and which ones don’t with this experiment. Supplies need include some newspaper, tincture of iodine (available at the drug store) and some cubes of foods that won’t spoil quickly such as some cut up pieces of fruit, cut up potatoes, squares of bread, cheese, cucumber slices, celery, and other light colored foods.
1. Place the food slices on the newspaper. Working with one food item at a time, have your student guess whether the food item has starch or not.
2. Squeeze a tiny drop of iodine on the food slice.
3. The iodine will turn purple with the starchy food items.
Bendy Turkey Bones: Is it possible to bend a bone without breaking it? You bet! While this experiment can be done with turkey bones and a few weeks time, for the quickest results, identically sized chicken wing bones work best. Also needed are a couple of pint jars (with lids), and some vinegar.
1. Preset the experiment at home by removing all the little bitty pieces of meat and cartilage off the bone. Scrub thoroughly, then bring to your classroom with all the supplies.
2. Have your students test the strength of the bones.
3. Place each bone in a single jar. Cover one with water, and one with vinegar. Label and let set for 2 days.
4. Carefully remove the wings. Rinse with water.
5. Have your students try to bend the bones to see what happens.
The science behind this experiment is that the vinegar reacts with the calcium carbonate in the bones, resulting in tiny little bubbles that rise to the surface. These bubbles is the carbon leaving the bone, and when this happens, the bones can be bent in half. This experiment shows how important calcium carbonate is for keeping bones strong.