SciTech

Students can learn chemistry through cooking tasty food

Students in Das’ chemistry course, Kitchen Chemistry Sessions, create food while learning about chemistry concepts behind cooking. Above is a dessert sushi of strawberry sheets with couscous, chocolate chantilly, caramelized peaches, prepared by sophomore chemistry major Alessandra Zimmermann. (credit: Courtesy of Alessandra Zimmermann) Students in Das’ chemistry course, Kitchen Chemistry Sessions, create food while learning about chemistry concepts behind cooking. Above is a dessert sushi of strawberry sheets with couscous, chocolate chantilly, caramelized peaches, prepared by sophomore chemistry major Alessandra Zimmermann. (credit: Courtesy of Alessandra Zimmermann) Credit: Frances Soong/Art Staff Credit: Frances Soong/Art Staff

Cooking is usually portrayed as an elaborate art. A measure of craft, a spoonful of inspiration, and a dash of creativity are combined in the creation of some of the finest pieces of culinary art. But in addition to the artistry, there is a lot of science behind the dishes — molecules interacting with other molecules, creating the combinations of taste and texture that hungry consumers appreciate the most. One professor at Carnegie Mellon has a base of knowledge in both culinary methods and the science behind it, so he decided to create a class to teach science through the art of cooking.

Subha Das, an assistant professor in the department of chemistry, has been enthusiastic about cooking nearly his whole life. When he’s not cooking, Das is researching the structure and function of nucleic acids — an activity that may seem completely different from cooking at first glance. He, however, argues that these two activities are synonymous. “As a practicing scientist in my lab, I’m an organic chemist. I’m synthesizing things, making things. I can do that because I have a good prior knowledge of the way those molecules work. But it’s no different than with food,” he said.

Das’ idea of teaching chemistry through cooking originated many years ago. With the support of his colleagues and department, he held his first chemistry and cooking class, titled “Kitchen Chemistry Sessions,” in the fall semester of 2009. He offered two slightly different renditions of the class — one for first-year non-science majors who had nearly zero background in organic chemistry, and one for students who already had substantial exposure to organic chemistry. The overall goal of the two classes was common: Teach chemistry by means of cooking.

“My idea is to teach chemistry using the context of food, and once you learn the chemistry and the underlying science principles, you can in fact be much more creative in what you do,” Das said. Students learned the scientific principles first, and then applied them by creating dishes they could try and share with other students. Keeping true to the similarities to working in a lab, all students were required to maintain a lab notebook. The class, which was designed to run for half a semester, covered numerous chemistry topics such as lipids, carbohydrates, and aroma-volatiles.

Sophomore chemistry major Alessandra Zimmermann said, “The focus of the class was on molecular gastronomy, which is basically the form of gastronomy that utilizes chemistry the most. And we did learn cooking techniques quite a bit, too.”

The course gave students some useful tricks for creating healthy foods with ease. In many instances, it is less convenient to make and eat healthy, nutritious foods; it takes more time, and in some cases, more money. Alternative, less-healthy foods usually have numerous chemicals added to them and undergo a lot of processing to give them the taste that people desire. Das’ class enabled students to create healthy foods that taste as good as processed ones. For example, one group of students made a chocolate-walnut milkshake with 2 percent milk instead of whole milk. Despite the low fat content of the milk used, their shake was very thick and creamy with the addition of xanthan gum as a thickener.

Zimmermann described another interesting class project. “We made fruit caviar, which is essentially just fruit juice mixed with a form of string polymer that forms a bubble; that was a very exciting class,” she said. “Also, our last class was on taste. So basically we just tasted lots of different things and [Das] explained to us how our body reacts to it.”

Sticking with non-traditional teaching methods, Das designed the final exam to be a student cook-off. Students were instructed to create a unique dish given basic guidelines on what types of ingredients their dish must contain. Their evaluation depended on the taste and appearance of their dish, as well as the science behind its creation. Das evaluated the dishes alongside a panel of other judges that consisted of various faculty members from the departments of chemistry, biological sciences, and art for a well-rounded perspective on the quality and creativity of the dishes.

The students were able to create interesting and scientifically intriguing dishes for the final, which was very pleasing to Das as the professor. Not only had the students successfully implemented chemical principles to create unique dishes, but they also showed that the science behind it actually enhanced the dishes. This was shown when the panelists’ approval of the dishes actually increased after the students explained the science that went into them.

When asked if she would recommend the class, Zimmermann stated, “I’d definitely recommend it to anyone who likes cooking, because it does expand your repertoire, and you learn a lot more about what you’re actually doing, instead of, ‘Let’s throw this together and hope it turns out okay.’ ”

According to a press release on www.cmu.edu, Das went on to present his successful idea at the 239th meeting of the American Chemical Society in San Francisco in March. Through this direct connection between science and food, Das was very satisfied with what he was able to teach and what the students were taking away from the course. “I can give students enough information to navigate the world that they’re in contact with. For me, that’s important. That’s the point of education,” he said.