The inspiration for this experiment comes from some brand new research in what happens when bubbles pop. Now this may not sound like its cutting edge or brand new, but just this year researches from Harvard published some exciting findings about a two stage process that forms new bubbles from larger ones. I have put together some easy experiments that you can do at home or in the classroom that demonstrate their findings. What’s even better is we get to eat our findings afterwards!
First we always gather all of our equipment and ingredients.
Straws
Large mixing bowl
Small mixing bowl
Measuring spoons
Measuring cups
Wisk or an electric beater
Cookie sheets
Parchment paper
OvenIngredients:
2 teaspoons dish soap
1 cup water
1 cup egg whites (the liquid ones will be easiest plus they are pasteurized)
½ cup regular sugar
Optional: chocolate chips, 1 teaspoon extract like vanilla, mint or orange, 2 tbsp. cocoa powder
Now for the real fun. Using what we have learned about making small bubbles we are going to make meringue cookies. Meringue cooks are very light and crispy because they are made up of very very little bubbles of air surrounded by egg whites. We use egg whites and sugar so that we can bake them, they don’t collapse and they taste yummy.
Begin by preheating an oven to 350 degrees. Remember always ask an adult for help when using an oven.
Soft peaks |
Line the cookie sheets with the parchment paper and put spoonfuls of the egg white mixture onto the cookie sheets. Try to make even spoonfuls and space them about an inch apart on all sides.
Place the cookie sheets in the oven carefully to avoid burns, close the door and turn off the oven. It will take several hours to overnight to for the cookies to become completely crispy. Do not turn the oven back on; this will cause them to burn. Just keep the door shut for at least 4 to 6 hrs. The cookies should be nearly or entirely white with little or no brown spots.
When the cookies are completely crisp remove them from the paper and store in an air tight container, the suck up moisture very easily and will become soggy. Enjoy!
More to Explore:
Pastry chefs have known for centuries that warm egg whites whipped in a copper bowl whip up faster and produce more volume. As a rule of thumb one egg white (about 1 oz) produces one pint, or 16 oz of meringue. But, with a little chemistry we can increase this two-fold. The copper bowl gives off copper ions that help the proteins bind to one another. Most of us do not have copper bowls in our kitchen, but we can find copper at the pharmacy in pill form. These pills contain copper gluconate, a ready source of copper ions. Using just a very small pinch of this will help whip up your eggs; too much though will make them taste funny. Another hindrance is the amount of water present in egg whites. While whipping you can use a water mister bottle and carefully increase the amount of water slightly and thus increase the volume of foam. This unfortunately makes a foam that collapses easier, so is not suitable for meringue cookies. Measure how much foam you can produce without any additives, than try it with just copper added, just water added and both added together to see how much meringue you can get from one egg white.