There is no wonder why nobody can resist marshmallows. They are soft, sticky, spongy, and sweet. And to add to that is the appealing colors that kids and adults alike love. In fact, having a campfire is not complete without skewered marshmallows.
With the unique properties of this confectionery, you have probably once asked yourself what makes marshmallows light and fluffy. Well, the early versions of this sweet treat were different from what we enjoy today.
MARSHMALLOWS’ INTERESTING BEGINNING
Marshmallows were originally made with the marshmallow herb (Althaea officinalis). It is a weedy relative of the mucilaginous hollyhock, which thrives in marshes. Some plants and microscopic animals create mucilage, a thick, glue-like secretion that aids in seed germination and food storage. The herb was employed by ancient civilizations for both culinary and medicinal uses. For instance, the French, who first saw the root in the early to mid-1800s, experimented with utilizing its sticky juice to cure sore throats. The ancient Egyptians dried the root and combined it with honey to produce mallow sweets.
The process of combining sap from the marshmallow plant with eggs, sugar, and whipping the mixture into a foam was initially used by the French to create “marshmallows” that resemble the sweets we now enjoy. Due to the high demand for marshmallows in the late nineteenth century, candy manufacturers were unable to keep up with the demand. In response, the marshmallow as we know it today was created, which is completely does not use the mallow herb.
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This early form of marshmallow used egg albumen, which served as a foaming and gelling agent. This resulted in a light, soft gel.
Today, candy makers use gelatin, which acts as a whipping and gelling agent. A marshmallow made of gelatin is heavier than one made of egg albumen yet is soft and springy. Warm gelatin sol may be beaten to three times its original volume since gelatin is a good foaming agent. Gelatin solidifies or forms a gel when it is cooled, trapping the air bubbles and stabilizing the mixture.
HOW MARSHMALLOWS ARE MADE
As I already mentioned, modern marshmallows are made with gelatin mixed with sugar syrup (sugar and corn syrup or honey and glucose) and then cooked. By whipping the mixture, foam is created, which is 2 to 3 times larger than the original volume. As the liquid cools and gelatin hardens, millions of air bubbles are stabilized and bound by the protein molecules. Pectin, agar, and starch are other gelling agents that all produce a soft, short-textured gel. These gelling agents have the benefit of being made from vegetable materials, but they also typically require a whipping agent.Â
As you already imagine now, a marshmallow is a solid foam that has a density that is just 35–45% as that of water.
If you wish to make marshmallows at home, there are several things to keep in mind. The key to making marshmallow that sets into a gooey consistency is heating the sugar to a temperature of 250ºF (121ºC) to produce a dense syrup.
The sugar to use is important. The walls of the air bubbles of the foam are strengthened by the thick, sugary syrup. If the amount of sugar is insufficient, the consistency will be affected, and make the marshmallows a mousse-like jelly. It is best to use a mix of sugar. Honey and glucose, for example. This makes sugar to be less likely to crystallize and make the marshmallows gritty.
While marshmallows are a foam, the beating process can make or break it—under or overbeating the mixture will affect the texture. The mixture has to be thick and forms soft peaks. This ensures a light and fluffy consistency.
What are foams, anyway?
Food foams are made up of aqueous continuous phase and gaseous (air) scattered phase. This is how whipping egg whites turns them into a foam.
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Many processed foods are compounds that resemble foam. These include marshmallows, whipped cream, ice cream, cakes, meringue, bread, and souffles. Their distinctive mouthfeel and textural qualities are a result of the distributed microscopic air bubbles as a result of of whipping or mixing. The primary surface-active ingredients in the majority of these products are proteins (gelatin), which aid in the creation and stabilization of the dispersed gas phase.
The texture of marshmallows can be altered by changing the ratios of the ingredients and the amount of whipping. More whipping will result in a softer marshmallow and more air bubbles being incorporated into the foam. Furthermore, the bubbles whipped in make the marshmallows to taste sweeter because the sugar molecules get into contact with the tongue much faster.
Although they might be delicious on their own, these marshmallows do not have a hard enough texture to be coated with chocolate or another type of candy. The good thing is that roasting marshmallows over a campfire makes them taste so much better. This is because the heat of the fire causes the gelatin to melt and the sugar to caramelize, creating a hot, gooey, caramel-flavored treat.
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In the factory
Marshmallow factories use the same method we use at home. A mixture of sugar and gelatin is made, cooked at 240°F (115°C) and then cooled to 151°F (66°C). The gelling and whipping agents are then added. The mixture is then delivered into a continuous whipping machine, where the aerated product is colored and flavored while being whipped with air or gas under high pressure. The mixture is then extruded and exposed to atmospheric pressure, causing it to expand. The rope of marshmallow is then laid on a conveyor belt, cooled, and cut to length.
Most types of marshmallows have a 1 x 1 inch cylindrical form. This is because liquid foam is usually extruded through a 1 inch diameter tube as it cools. The marshmallow rope that emerges from the tube is sliced into pieces about 1 inch long.
References:
M. Wallert, K. Colabroy, B. Kelly, J. Provost (2016). The Science of Cooking: Understanding The Biology And Chemistry Behind Food And Cooking. John Wiley & Sons, Inc..
S. Farrimond (2017) .The Science of Cooking: Every Question Answered to Perfect Your Cooking. DK Publishing
W. P. Edwards (2000). The Science of Sugar Confectionery. The Royal Society of Chemistry.
S Damodaran, K. Parkin. (2017) Fennema’s Food Chemistry (5th edition). CRC Press.
