GOOD EATS: MARSHMALLOW CHEMISTRY
Editor’s note: In this exploration, Sophia P. (‘19) explores the chemistry as well as the recipe of marshmallows.
Marshmallows are a nostalgic treat that most associate with lovely memories of childhood: sipping hot cocoa with mini marshmallows by the fire, roasting marshmallows while making s’mores, or baking tasty rice krispy treats. However, what most neglect is how the processed taste of Kraft or other store-bought brand marshmallows don’t nearly compare to the natural, sweet taste of homemade ones. Alton Brown, a famous chef, actor and food show presenter, explores his appreciation and the chemical process behind making the perfect marshmallow in season eleven, episode 12, “Puff the Magic Mallow” of his Food Network TV show, Good Eats.
Brown begins the episode by providing basic information behind marshmallows; explaining how ‘marshmallow’ is a plant, which in ancient times was utilized as a cure to many diseases. In order to make this candy from scratch, there is an extensive process, yet the fresh smell and taste of the homemade marshmallow makes the methodology worth it. The first step is to mix three packages of gelatin and half of a cup of cold water together. The cold temperature of the water is necessary because the gelatin won’t dissolve into the hot solution unless you mix it with cold water first, making it “bloom”. “Blooming” is a process where you add cold water to gelatin in its powder form, and it absorbs the water, causing the particles to expand. This is a necessary step before melting the gelatin in the sugar solution. If you don’t “bloom” the gelatin, it won’t properly mix with the sugar syrup (What’s Cooking America).
The next step is to pour ½ cup of water, 1-½ cups of sugar, 1 cup of corn syrup, and ¼ teaspoon of kosher salt in a saucepan and leave this on medium/high heat with the lid on the pan for three to four minutes. In order to give the marshmallow its squishy, soft, shape, you can’t use only regular table sugar like in other candies; Regular, white sugar will make the marshmallow hard, like rock candy, and therefore not be the gooey texture you love to bite into. In order to achieve the proper consistency of a marshmallow, you must use high fructose corn syrup, to prevent the sugar from crystallizing and making the candy rocklike (Ghee, 2007, p. 680). But you might wonder, how is fructose corn syrup sweet if corn is not? To understand this, you must have a basic understanding of sugar or sucrose. Sucrose is cane sugar made up of glucose and fructose. Glucose is not sweet, while fructose is extremely sweet; half of the honey we eat is made up of fructose (Wolke, 2006). Corn syrup is mainly strands of starch, which is made of a chain of glucose that interferes with the sugar (Ghee, 2007, p. 678). In order to make candy, the sugar needs to be in liquid or syrup form to prevent it from crystallizing and ruining the soft texture. So, the high fructose corn syrup becomes sweet through an enzyme process. Glucose takes an enzyme and turns it into fructose, the sweet molecule. The point of having the fructose is to make the sugar sweet, and the point of glucose is to prevent the sugar from solidifying (Ghee, 2007, p. 678).
The recipe calls for heating this mixture of water, corn syrup, sugar, and kosher salt until the water boils. Water alone boils at 212°F, but if you add something that dissolves into water it causes the mixture to need to reach a hotter temperature in order for it to boil. This is because as you boil the sugar syrup, the water boils out of the solution, therefore there is more sugar per molecule of water. As the concentration of sugar becomes higher, the water needs more energy to boil meaning a higher temperature (Ghee, 2007, p. 680). The outcome of the candy formed is determined by the amount of sugar in the syrup. There is a 85% concentration of sugar in the solution used to make marshmallows, explaining why you would need to boil the solution at a higher temperature than just water alone (Buddies, 2012). The boiling point when cooking the syrup for marshmallows is 240°F, which is actually a lower boiling point compared to solutions of other candy (Ghee, 2007, p. 684).
After letting the solution heat up for three to four minutes, take the lid off of the saucepan, and wait seven to eight more minutes for the solution to boil. Once it has hit 240°F, mix the gelatin using a stand mixer set at a low speed, (notice how the gelatin has bloomed), and then slowly and carefully pour the syrup into the sides of the bowl. Once all of the syrup is in the bowl, turn the speed of the mixer up to “high” for 13 to 15 minutes to get as much air as possible into the marshmallow. When the mixture is one minute from done mixing, add one teaspoon of vanilla extract. Use a metal, 9x13” pan to bake the marshmallows, and grease the pan with a non-stick spray. Because the marshmallow is so sticky, you will also need to create a mixture of ¼ cup of confectioners sugar and ¼ cup of cornstarch. Dust some of the mixture onto the pan, and then cover it with aluminum foil, and shake the pan to prepare it completely. After taking the aluminum foil off, use an oiled spatula to move the marshmallow into the pan and smooth it out. Sprinkle some more cornstarch and confectioners sugar on top of the marshmallow, and once it reaches room temperature, put aluminum foil over it. Next, let it sit for a minimum of four hours, or for the best results, overnight. When at least four hours have passed, flip the marshmallow out of pan and cut it using a pizza cutter into evenly sized squares. Finally, dust more sugar and cornstarch onto the sticky edges, and your marshmallows are done!
Whether you are making them for fun or a specific dessert, there is no treat like homemade marshmallows. Although the process may seem tedious, the final product outweighs the work. Enjoy!
Citations
Buddies, S. (n.d.). Sweet Science: Making Marshmallows. Retrieved December 15, 2016,
from https://www.scientificamerican.com/article/bring-science-home-marshmallows/
Brown, A. (Writer), & Gyoury, C., Brown, A. (Directors). (2007, December 3) Puff the
Magic Mallow ep.16 In Good Eats Collection. Food Network. Collection. Food Network.
Gelatin Cooking Tips, What’s Cooking America. (n.d.). Retrieved December 15, 2016, from ‘
https://www.bing.com/cr?IG=0953C63BAEBC497A90DD048D5051F064&CID=03929
EF7545E6545214E971B556F64E9&rd=1&h=F2BCWahgiBZcNV2ucPLtNA9kHTl8pDl7QHcZ7LYJa3Y&v=1&r=https://whatscookingamerica.net/gelatintip.htm&p=DevEx,5083.1
McGee, H. (2004). On food and cooking: The science and lore of the kitchen. New York:
Scribner.
Wolke, R. L. (2006, March 29). Sweet Talk. The Washington Post. Retrieved December 07,
2016.
White, D., Lawson, N., Masters, P., & McLaughlin, D. (2017). Clinical chemistry. New York,
NY: Garland Science/Taylor & Francis Group.
Brown begins the episode by providing basic information behind marshmallows; explaining how ‘marshmallow’ is a plant, which in ancient times was utilized as a cure to many diseases. In order to make this candy from scratch, there is an extensive process, yet the fresh smell and taste of the homemade marshmallow makes the methodology worth it. The first step is to mix three packages of gelatin and half of a cup of cold water together. The cold temperature of the water is necessary because the gelatin won’t dissolve into the hot solution unless you mix it with cold water first, making it “bloom”. “Blooming” is a process where you add cold water to gelatin in its powder form, and it absorbs the water, causing the particles to expand. This is a necessary step before melting the gelatin in the sugar solution. If you don’t “bloom” the gelatin, it won’t properly mix with the sugar syrup (What’s Cooking America).
The next step is to pour ½ cup of water, 1-½ cups of sugar, 1 cup of corn syrup, and ¼ teaspoon of kosher salt in a saucepan and leave this on medium/high heat with the lid on the pan for three to four minutes. In order to give the marshmallow its squishy, soft, shape, you can’t use only regular table sugar like in other candies; Regular, white sugar will make the marshmallow hard, like rock candy, and therefore not be the gooey texture you love to bite into. In order to achieve the proper consistency of a marshmallow, you must use high fructose corn syrup, to prevent the sugar from crystallizing and making the candy rocklike (Ghee, 2007, p. 680). But you might wonder, how is fructose corn syrup sweet if corn is not? To understand this, you must have a basic understanding of sugar or sucrose. Sucrose is cane sugar made up of glucose and fructose. Glucose is not sweet, while fructose is extremely sweet; half of the honey we eat is made up of fructose (Wolke, 2006). Corn syrup is mainly strands of starch, which is made of a chain of glucose that interferes with the sugar (Ghee, 2007, p. 678). In order to make candy, the sugar needs to be in liquid or syrup form to prevent it from crystallizing and ruining the soft texture. So, the high fructose corn syrup becomes sweet through an enzyme process. Glucose takes an enzyme and turns it into fructose, the sweet molecule. The point of having the fructose is to make the sugar sweet, and the point of glucose is to prevent the sugar from solidifying (Ghee, 2007, p. 678).
The recipe calls for heating this mixture of water, corn syrup, sugar, and kosher salt until the water boils. Water alone boils at 212°F, but if you add something that dissolves into water it causes the mixture to need to reach a hotter temperature in order for it to boil. This is because as you boil the sugar syrup, the water boils out of the solution, therefore there is more sugar per molecule of water. As the concentration of sugar becomes higher, the water needs more energy to boil meaning a higher temperature (Ghee, 2007, p. 680). The outcome of the candy formed is determined by the amount of sugar in the syrup. There is a 85% concentration of sugar in the solution used to make marshmallows, explaining why you would need to boil the solution at a higher temperature than just water alone (Buddies, 2012). The boiling point when cooking the syrup for marshmallows is 240°F, which is actually a lower boiling point compared to solutions of other candy (Ghee, 2007, p. 684).
After letting the solution heat up for three to four minutes, take the lid off of the saucepan, and wait seven to eight more minutes for the solution to boil. Once it has hit 240°F, mix the gelatin using a stand mixer set at a low speed, (notice how the gelatin has bloomed), and then slowly and carefully pour the syrup into the sides of the bowl. Once all of the syrup is in the bowl, turn the speed of the mixer up to “high” for 13 to 15 minutes to get as much air as possible into the marshmallow. When the mixture is one minute from done mixing, add one teaspoon of vanilla extract. Use a metal, 9x13” pan to bake the marshmallows, and grease the pan with a non-stick spray. Because the marshmallow is so sticky, you will also need to create a mixture of ¼ cup of confectioners sugar and ¼ cup of cornstarch. Dust some of the mixture onto the pan, and then cover it with aluminum foil, and shake the pan to prepare it completely. After taking the aluminum foil off, use an oiled spatula to move the marshmallow into the pan and smooth it out. Sprinkle some more cornstarch and confectioners sugar on top of the marshmallow, and once it reaches room temperature, put aluminum foil over it. Next, let it sit for a minimum of four hours, or for the best results, overnight. When at least four hours have passed, flip the marshmallow out of pan and cut it using a pizza cutter into evenly sized squares. Finally, dust more sugar and cornstarch onto the sticky edges, and your marshmallows are done!
Whether you are making them for fun or a specific dessert, there is no treat like homemade marshmallows. Although the process may seem tedious, the final product outweighs the work. Enjoy!
Citations
Buddies, S. (n.d.). Sweet Science: Making Marshmallows. Retrieved December 15, 2016,
from https://www.scientificamerican.com/article/bring-science-home-marshmallows/
Brown, A. (Writer), & Gyoury, C., Brown, A. (Directors). (2007, December 3) Puff the
Magic Mallow ep.16 In Good Eats Collection. Food Network. Collection. Food Network.
Gelatin Cooking Tips, What’s Cooking America. (n.d.). Retrieved December 15, 2016, from ‘
https://www.bing.com/cr?IG=0953C63BAEBC497A90DD048D5051F064&CID=03929
EF7545E6545214E971B556F64E9&rd=1&h=F2BCWahgiBZcNV2ucPLtNA9kHTl8pDl7QHcZ7LYJa3Y&v=1&r=https://whatscookingamerica.net/gelatintip.htm&p=DevEx,5083.1
McGee, H. (2004). On food and cooking: The science and lore of the kitchen. New York:
Scribner.
Wolke, R. L. (2006, March 29). Sweet Talk. The Washington Post. Retrieved December 07,
2016.
White, D., Lawson, N., Masters, P., & McLaughlin, D. (2017). Clinical chemistry. New York,
NY: Garland Science/Taylor & Francis Group.
