Cooking and Chemistry in 8th Grade
Ice cream, cookies, hot dogs, and homemade soup…Sounds like we’re about to do some Organic Chemistry!!!
The purpling sky has given way to another cold wet night in Portland Oregon, and the wind is peppering the windows with, from what we can hear, is changing quickly from hail to sleet to cold rain. Time to brave the weather to grab some herbs from the yard and cozy up by the stove for some Organic Chemistry. I’ll explain what I mean.
Throughout the years our students have had learning experiences with farming, botany, cooking, and combustion, but this is the year we bring them all together in fun and delicious ways during my favorite block, organic chemistry.
The study of chemicals is the study of what all things are made of since everything is made of chemicals, molecules, and, ultimately, atoms. Those things are too small for us to see with our eyes, but our senses can teach us a lot about how things are structured. Since our curriculum is all about storytelling and experiential learning, there is no better place than the kitchen to peer into the world of organic chemistry.
After a month of stories and labs, we are ready to make soup. This is where it all comes together. We have learned that all living things, including us, are made of a handful of important elements, or kinds of atoms. Nitrogen, hydrogen, and oxygen form bonds around the structure of carbon and we as carbon-based life forms are always looking for those elements to constitute our bodies in the form of food. Talking about chemistry always makes me hungry.
There are four tried and tested ways of speeding up chemical reactions, and we may need all of them for this project. The thing is soup is made of many organic chemicals, mostly carbohydrates in different forms, cellulose, and starches from the cells of plants, which are long-chain carbohydrates and can be broken down to delicious monosaccharides (simple sugars) to be used by the body.
If left to their own devices they would undergo the same kinds of chemical changes while being broken down by bacteria, but that would take a long time and we would end up with compost instead of soup. So if we want dinner we will need to speed up these reactions. We just need to apply heat, and catalysts, after we increase the surface area and, if possible, increase the pressure to speed things up even more.
By cutting up our potatoes and carrots we are exposing more surface area to the water so there are more places for the chemical reactions to occur. We rarely make soup with whole potatoes right?
Then we need to turn up the heat. Heat causes the molecules to move around faster and breaks the bonds between those long-chain starches stored in the root vegetables. Oil in the pot can raise the temperature even higher than water since water experiences a state change and turns from a liquid to a gas at 100 degrees Celsius, but oils have a much higher range of temperatures that they can remain liquid through. This means our bitter onions get to caramelize with the help of oil, literally turning into sugars, a chemical change we can see and smell. Mmmmm!
Next add some herbs from the garden. They have been storing complex chemicals in their leaves, through the process of photosynthesis, and we can smell the aromatics of essential oils evaporating in the heat. Yum!
Then we add catalysts in the form of sodium chloride, or salt. Salt is a strong catalyst for speeding up oxidation and other chemical reactions. Think about the last time you were at the beach. Did you ever notice how metal in ocean water seems to rust faster than in freshwater lakes? Salt also increases the chemistry of our taste buds to let us enjoy the food more. Drool!
Finally, if you have an instant pot or pressure cooker, you can increase the pressure and that is going to get dinner on the table in record time. This is great because chemistry really works up an appetite. Enjoy!
Written by Jacob Wooton. Mr. Wooton has been working in education for two decades almost half of which has been here in the enchanted halls of Cedarwood. His hope is to foster a sense of inner strength and independence in his middle school students. His motto is " work hard, be kind. " He is sometimes called a math teacher, but really he coaches creative problem-solving with applied math skills. He graduated from Evergreen State College and completed his Masters of Arts in Teaching at Lewis and Clark, and has committed himself to hundreds of hours of Waldorf-specific teacher training in science, math, and child development. He has two awesome kids of his own, who make him very proud every day. When not teaching algebra, he paints, a lot, and makes comic books a little.