Ah, Thanksgiving. A day full of turkey, cranberries, pie, and, of course, SCIENCE! Thanksgiving is a classic American holiday when families gather around the dinner table. Along with providing an opportunity for family members to celebrate, this holiday also serves as the perfect occasion to impress others with these fun, holiday-themed science facts.
The True Culprit Behind The “Turkey-Day Coma”
For eons upon eons (or at least the past few decades), we’ve blamed post-Thanksgiving drowsiness on tryptophan, an amino acid found in turkey meat. Is this really fair or should we be pointing our fingers somewhere else? Perhaps somewhere closer to our empty plates and full bellies? Tryptophan indeed is linked to drowsiness – that’s no myth. It’s a biochemical precursor to serotonin, which has a calming effect on the brain and body. And tryptophan is indeed found in turkey meat. It’s also present in chocolate, some fruits, dairy, red meat and eggs. However, tryptophan is almost certainly not the cause of the Turkey Day food coma. First of all, the levels of tryptophan that we ingest in even a Thanksgiving-sized portion of turkey is not all that much more than is found in what we eat on any other day. Plus tryptophan works best on an empty stomach, not a stuffed one! The real culprit? It’s probably a combination of your body working hard to digest a large meal and a fervent desire to put off doing the dishes!
From Sauce to Solid: The Science of Cranberries
“Slurp…plop!” Recognize that sound? You might if your family usually serves jellied cranberries on Thanksgiving. Cranberries have been known to help fight cancer and also contain antioxidants and nutrients that are beneficial to both dental and cardiovascular health as well as anti-aging properties. Cranberries can be served as a sauce – some like it runny; others like it wiggly; and still some like it firmly gelled. No matter which version you prefer, they all have the exact same ingredients – water, sugar and cranberries.
So what makes one version turn into a gelatin while the other stays saucy? It all comes down to the cooking time & how it affects the natural pectin found in the cranberry. As they are cooked, the cranberries pop open, releasing pectin, which helps them stick together. Pectin is a natural polymer found in between plant’s cells and within the cell walls. It helps “glue” the plant cells together and keeps plant tissues firm. And in cooked cranberries it can help stick the cooked fruit together to form a solid jelly. Jellied cranberries are thick, like gelatin, and retain the shape of the mold in which it was placed, which might mean Aunt Sallie’s turkey mold or even the shape of a can. If you are looking at a way to please everyone at dinner by serving both gooey and jellied cranberries, head into the kitchen & discover the science of cranberries for yourself!
Thanksgiving would not be the same without mashed potatoes. Not only do they go great with turkey and gravy, they conduct electricity too. Potatoes have hidden energy that can turn your thanksgiving side dish into a real, working battery!
The potato battery is a type of electrochemical cell that demonstrates current electricity. An electrochemical cell converts chemical energy into electrical energy. In the potato battery, there is a transfer of electrons between a galvanized nail and copper wire that is inserted into the potato. The potato conducts electricity, keeping ions separate, so that the electrons in the copper wire are forced to move generating an electric current. It’s not enough power to shock you, but the potato can generate readings on electricity meters, make light bulbs glow and even power small digital clocks. You can super-charge your spuds this Thanksgiving by making your very own potato clock!
The “A-Maiz”ing Ear
We can’t talk about the traditional Thanksgiving meal without mentioning corn! Known as “maize” to Native Americans, the relationship between corn & Thanksgiving go all the way back to the first harvest time celebration feast in Plymouth. Whether in a creamy custard or casserole, corn dishes add a little more sweetness and richness to our decadent meal. Corn is grown on every continent except Antarctica and is by far, America’s number one field crop.
Not only does it provide great nutritional benefits for us but it has many uses in our everyday life including corn starch, popcorn, corn syrup, corn plastics, and of course, ethanol. One bushel of corn can make 32 pounds of starch, 33 pounds of sweetener, 2.8 gallons of ethanol fuel and 1.6 pounds of corn oil. Ethanol is an alcohol-based fuel, also known as biofuel, which is produced from the ears of the corn plant. Ethanol can power cars and also be used as cooking oil. Biofuel burns cleaner than gasoline, reducing air and water pollution. As you bite into that juicy ear of corn during your Turkey Day feast, use some of these facts to “a-maize” your dinner guests with the surprising versatility of plain old corn!
Get Saucy with Starches
Who doesn’t love soaking up the last bit of gravy on Thanksgiving? Sauces provide concentrated flavor in a thickened liquid form that compliments the rest of your meal. No matter if they’re salty, spicy, savory, or sweet, sauces make foods richer and more enjoyable! There are many ways to thicken sauces, but one of the most common ways is to use starches. Cooks have two choices in deciding how to thicken sauces with starches: they can use the starches from grains, or the starches from tubers and roots. The starch in grains like wheat, corn, and rice is different from the starch in roots and tubers like potatoes, tapioca, and arrowroot.
To make your sauce or gravy you add the starch to the liquid. It sounds like a simple task – You just put it in, right? Wrong. Mixing starches & liquids can be a very tricky process. There are several methods to incorporate the two together, including mixing the starch first with a small amount of cold water, mixing the starch first with a bit of fat, or making a roux. By experimenting with different starches and liquids, you can watch the molecules go to work & discover which has the ultimate thickening power!
Perfecting Your Pumpkin Pie
Pumpkin pie is one of the staples of the Thanksgiving feast, having been linked to the holiday since that autumn eve more than 300 years ago. Pumpkin pie has even sparked the interest of archaeologists as a product derived from merging three distinct cultures together. This favorite holiday dessert is a combination of ingredients from Native American, European and African cultures – pumpkin, pastry crust and allspice- and represents a cultural mixing referred to as “creolization” by New World Scholars.
Pumpkin pie not only attracts archaeologists around the world but kitchen scientists as well. You can enjoy this dessert on its own or with a dollop of whipped cream, but either way the light & flaky crust is crucial in producing a perfect pumpkin pie. Making the dough light & flaky all comes down to the scientific makeup of the pie dough. When making pastry dough, large amounts of fat are used to coat and separate the flour particles from each other. You then add just enough water to make a dough. Since much of the starch in the flour is not in contact with any of the water, the resulting cooked dough is crumbly and flaky. If the pastry that surrounds the pumpkin mixture is heavy or chewy then that can affect how much you enjoy this thanksgiving finale. This holiday, experiment with different fats & temperatures to see which gives your pumpkin pie the best texture & taste. Who knows, with the help of a little science, you just might become your family’s pie master!
For many families, Thanksgiving Day is marked by special foods — and endless leftovers. If you’re on kitchen duty this November, put these food science skills to use & become a kitchen chemist with experiments like these!