Today’s Wonder of the Day was inspired by Zachary from Muncie, IN. Zachary Wonders, “What are marshmallows made out of? ” Thanks for WONDERing with us, Zachary !

Do you like to go camping? It can be a lot of fun to sleep in a tent and cook your meals over a campfire. Of course, the best thing about starting a campfire is dessert. Graham crackers? Check! Chocolate bars? Check! There's only one more thing you need to make tasty s'mores: marshmallows!

Ooey, gooey roasted marshmallows melt the chocolate and cement the graham crackers together into a warm, tasty treat unlike any other. What exactly are in those marshmallows, anyway?

If you put together a recipe for marshmallows, you might expect it to include things like one cup of deliciousness, two tablespoons of pure joy, a pinch of sweetness, and four hairs from the tail of a unicorn. Instead, the list of ingredients on a package of marshmallows reveals a variety of ingredients you may already be familiar with.

That wasn't always the case, though. Modern marshmallows trace their roots back to the marshmallow plant — Althea officinalis — that the ancient Egyptians used as a medicine to treat sore throats. After crushing the plant's roots to create a paste from their sap, they boiled the paste with honey or sugar syrup to make a chewy substance that could be eaten like candy.

French candy makers took things a step further in the 19th century when they began to whip the sap of the marshmallow plant into a fluffy candy that more closely resembled modern marshmallows. It was expensive and time-consuming to extract the sap from marshmallow plants, though, so clever bakers looked for alternatives.

Eventually, marshmallow plant sap was replaced with egg whites and gelatin. This substitution allowed American inventor Alex Doumak to invent a fully-automated process to make marshmallows in 1948. His process created marshmallows with the familiar cylindrical shape we know today.

Although recipes vary amongst manufacturers, the most common ingredients in modern marshmallows are gelatin, egg whites, corn syrup, sugar, and flavorings, such as vanilla. Marshmallows are often coated with a mixture of powdered sugar and corn starch to keep them from sticking together.

Today, marshmallows remain a popular candy that can be found in all sorts of shapes, sizes, flavor, and colors. In addition to s'mores, marshmallows are a popular part of many breakfast cereals. They also make a great addition to hot chocolate.

Melted marshmallows turn plain Rice Krispies® cereal into a sweet treat kids love. You'll also find them topping sweet potato casserole and floating around in ambrosia salad. If you have a stick and a campfire, a roasted marshmallow is a delicious treat all by itself.

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Lace up your walking shoes! We’re hitting the road tomorrow in Wonderopolis!