Mad About Science: Pumpkins

By Brenden Bobby
Reader Columnist

It’s that time of the year where every coffee shop smells like one thing and one thing only: pumpkin spice. It’s interesting that the smells involved with pumpkin spice actually have nothing to do with pumpkins, aside from being used to flavor them. None of the spices involved in pumpkin spice even originate from the same continent as pumpkins, yet here we are.

Courtesy photo.

Fun fact: pumpkin spice is a collection of a few different spices ground up together — namely cinnamon, ginger, nutmeg, cloves and allspice, all of which originate from Southeast Asia, and primarily Indonesia.

Pumpkins are a uniquely American fruit, and though their imagery is linked to a number of English and Irish harvest celebrations, the British Isles had no idea this particular squash existed until sometime in the 1600s. Despite their relative newness to Anglo-American culture, the Indigenous peoples of North America have used pumpkins as a food source for at least 9,000 years.

Pumpkins as we know them are a relatively new breed of squash — large, usually hollow and stuffed full of water, they’re bred to grow to enormous sizes and appear as a spectacle during late October and early November, only to rot into a disgusting mass before Christmas. The original pumpkin was a smaller fruit, much closer in size to the sugar pumpkins we use for pumpkin pie, but likely closer in appearance to other squash varieties we’ve seen like acorn squash, spaghetti squash or butternut squash, albeit with a much brighter orange husk.

In case you’re wondering why pumpkins are such a bright shade of orange, it comes down to a pigment that’s shared across a number of fruits and vegetables, including tomatoes and carrots. This pigment is called a carotenoid, and it forms after the green chlorophyll pigments the plant uses for photosynthesis begin to break down. This designates that the plant is generally no longer supplying energy to the fruit, and also signals to animals that the fruit is ready to be consumed with the intention of spreading the seeds far beyond the area where it was grown.

Did you know that every single part of a pumpkin is edible? Roasted pumpkin seeds are a popular snack, while the starchy flesh makes for tasty fall pies. Even the stem, the vine and the leaves are edible, which isn’t the case for many other fruiting plants. Pumpkin blossoms are used in some dishes, but can be eaten on their own or fried for a little crunch. Squash blossoms are occasionally featured on cooking competitions, where chefs stuff them full of something like cream cheese before deep frying into a kind of pumpkapeño popper.

A tasty pumpkin shares a key trait with other fruits and vegetables: The larger a pumpkin is, generally the worse it tastes. While it seems logical that larger fruits and vegetables have absorbed more nutrients and minerals that give them a delicious taste, the bulk of larger fruits and veggies is usually just an excess of water stored inside the plant. The amount of water-to-nutrients grows disproportionately once the fruiting part of the plant expands to excessive sizes — this is especially true of members of the squash family, of which pumpkins are a part. Zucchini is another squash that can rapidly grow to tremendous sizes, but rapidly loses flavor once it begins to balloon with water.

Of course, taste is all relative, and some folks prefer huge vegetables, especially when you want quantity for something like a fall soup that is mostly flavored by the spices and seasonings you put into it. However, the water content of carving pumpkins is largely why they don’t taste nearly as good as their sugary cousins that we puree into pie.

The history of pumpkin cultivation is an interesting one. The Indigenous peoples of North America used it as the foundation of what they called the “Three Sisters” technique. This method of cultivation used maize, beans and pumpkins growing together to compliment each other and help the others grow. The maize would grow tall to create a lattice network for the beans to climb, while the pumpkins would vine along the riverbanks to create a strong foundation for the other plants, absorb excess water from the river, outcompete weeds and keep the ground clear for the beans and maize — almost like an actively growing mulch. Unfortunately, pumpkins don’t store well after eight to 12 weeks, but other varieties of squash can store in proper conditions for months on end.

If you’ve made it this far, you’re probably waiting to hear about the history of jack-o’-lanterns. This is an Irish tradition that goes back to the 1800s, and began with a story about a mythological figure named Stingy Jack, a spiteful drunkard who liked to play tricks on people. Some variants of the story have him striking a deal with the Devil, others have him making spiteful wishes of an Angel, but all of them have him stuck on Earth in a form of bizarre purgatory where his only guiding light is a hollowed out turnip or pumpkin he must use as a lantern.

Really, I think it’s just fun to eviscerate a gourd and stick a candle inside.

Stay curious, 7B.