What Are Marshmallows?


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Whether you enjoy them in S'mores, atop a steaming cup of hot cocoa, or shaped like brightly colored bunnies or baby chicks, marshmallows are a staple of the modern candy landscape. 

But what are these sweet, fluffy treats, and exactly how are they made?

What Are Marshmallows?

Marshmallows are made by mixing sugar, corn syrup and water and bringing it to a boil. Then gelatin is added and the mixture is whipped to incorporate air. Additional ingredients can include flavoring and coloring. 

This raw material, a sort of sweet, sticky slurry, is then pushed through long tubes at extreme pressure, in a process known as extrusion. The extruded ropes of marshmallow are then cut into short, squat little cylinders and dusted with corn starch to keep them from sticking together. 

The process of making Marshmallow Peeps is quite a bit more complicated, but the ingredients are the same (with the addition of the brightly colored sugar coating). 

The History of Marshmallows

The original marshmallows were something quite different to what we're used to today. The ancient Egyptians boiled the root of a variety of mallow plant (Althaea officinalis) that grew in the marshes alongside the Nile river, and combined it with honey to produce the earliest known version of marshmallows. 

In 19th-century France, candymakers whipped the sap of the plant along with sugar and egg whites to produce something that more closely resembles the modern version, although today's marshmallows are not made using the Althaea officinalis plant, or, for that matter, with egg whites.

Modern Marshmallows

Until the 1950s, marshmallows were for made by hand, in a time-consuming process in which the marshmallows had to "sweat" for the several hours it took for them to develop their skin, before being dusted with starch. The breakthrough came when a candymaker developed the extrusion method we mentioned earlier, which not only automated the process but also pumped the marshmallows full of copious amounts of air, thereby imparting their characteristic squishy, fluffy texture.

Store-Bought Vs. Homemade

Like just about anything in the culinary world, there are two versions of marshmallows: the kind you buy at the store, and the kind you make yourself. Because yes! You can make your own marshmallows. They're not going to look the same as the store bought kind, since you don't have access to an industrial extruding machine. But the homemade kind will be every bit as light and airy and sweet, and possibly taste even better. 

The procedure involves cooking up a mixture of sugar, salt, water and corn syrup, along with a dash of vanilla extract, and combining it with gelatin and whipping it until it's light and fluffy, then pouring the mixture into a baking dish that you've dusted with powdered sugar. You'll also dust the top of the marshmallow. 

After it sets, you'll turn out the slab onto your cutting board and cut them into squares. You can then decorate them with sprinkles (the cut sides remain sticky), dip them in melted chocolate, or simply enjoy them plain. 

How Long Do Marshmallows Last?

The urge to refrigerate is a strong one, that can be difficult to overcome. And marshmallows are no exception. Yes, you can refrigerate your homemade marshmallows, especially if you like the way they taste when they're chilled.

But you don't have to. There's nothing in a marshmallow that needs cool or cold temperatures to stay fresh. Indeed, sealed in the bag, store-bought marshmallows will be just fine months past their use-by date. Marshmallow Peeps are known to get a bit crunchy as they age, which many consumers find preferable.

In terms of spoilage, considering that sugar, corn starch and gelatin and corn starch are all shelf stable, there is nothing in a store-bought marshmallow that can go bad. None of these ingredients, nor the marshmallows' low water content, will support the growth of bacteria.

After the bag is opened, however, moisture from the air can seep in and cause them to turn a bit sticky, sort of the way a muffin will start to get sticky after a few days. It's the same principle. To prevent this, keep them sealed tightly. You don't have to refrigerate or freeze them, though.

On the other hand, if you want to try frozen marshmallows, go ahead and seal them in an airtight container and freeze them to your heart's content.