The Inflated Appetite class. Photo credit: Rob Chron.

Inflated Appetite: An exploration of food as pneumatic shape-changing interfaces

By Lining Yao and Jifei Ou

Every January, when other schools are resuming classes after the holiday break, MIT does something a little different: the Independent Activities Period (IAP). No formal classes are held during this time; instead, the MIT community pursues learning endeavors based on their own interests and hobbies. Students, staff, and faculty offer how-to sessions to teach each other what they know, and this is a tremendous opportunity for all of us — not only to take a class that pushes our boundaries, but also to think about something we are passionate about in terms of how we would teach and explore it with others. The results of these classes are often surprising, not only to the people who participate but for the instructors as well.

Pneuduino. Photo credit: Jiffei Ou.

We’ve always believed that the kitchen is a great place for smart material invention. Our PhD research topic in the Tangible Media group, led by Professor Hiroshi Ishii, is related to one particular type of smart material: shape-changing materials. Shape-changing often requires a certain energy input, or stimuli. If we think about the process of cooking, it is all about utilizing the right energy stimuli to create the desired shape-changing, or transformation. When we bake stuff, boil stuff, fry stuff, or microwave stuff, we create transformations in food materials: the shape, color, texture, and other physical properties change, in a controllable and programmable manner. And the coolest part is, all those smart transformations are edible!

To material hackers and designers like us, the kitchen becomes a playground that offers an amazing material library, fabrication toolkits, and various forms of energy stimuli. With all those raw ingredients, so many magical food forms and flavors can be re-designed. We believe the combination of our research interests, students’ passion for food, and their creativity and cross-disciplinary backgrounds can bring true creation into the kitchen.

That is why we initiated our IAP class. Called Inflated Appetite, the class focused on the theory, design, and fabrication of pneumatic shape-changing interfaces, explored through experimenting with food. As the name of the course indicates, we explored how to inflate food, through either biological or mechanical means. When fermenting in a dough, for example, yeast creates carbon dioxide that makes our traditional bread soft and puffy. We developed a food plotter that cuts the dough into a designing shape to control the inflation. We also developed a pneumatic control toolkit, called Pneuduino, to blow the air into the food.

The bioLogic project. Source:

Both our team of instructors and the students came from across MIT. In addition to the two of us, the instructors included Dr. Wen Wang, a chemical and biological engineer in the department of Chemical Engineering; and Chin-Yi Cheng, a computational architect from the Department of Architecture. This team came together originally because of our shared passion for material design. We have been working together on a big research project, bioLogic, for more than a year. Although bioLogic has little to do with food, it has a lot to do with programmable and transformable materials, as well as digital fabrication. All of us happen to love food from different perspectives, and we share the same passion to bring our knowledge and academic backgrounds into kitchen. This IAP class, in a sense, was our experiment, and it turned out a completely new experience.

With our course, we aimed to bring together food, bio-design, material science, and engineering. We wanted to bring our research outcomes into the hands of MIT students who love food. The technical platform we provided included the electronic pneumatic control toolkits, and the food printer we developed. Ultimately, we hoped to create material magic in kitchen, not so much through training and experience, but rather through science and creativity.

The class started with four introductory lectures, covering food design, science of fermentation, pneumatic control, and computational design. Food-making has been always a hands-on process, so we kept the lectures concise and left students enough time to play with different food materials. With the basic knowledge from these four lectures, they explored sugar, ice cream, cheese, chocolate, and other food materials. Each day we gave students conceptual and technical feedback on their new experiments, helping them to implement ideas towards the goals of developing a showcase for a final reception. Most of the students joined the class because of their passion for food and cooking. It was so interesting to see how they combined the inflating techniques and digital fabrication tools with the food materials that they were familiar with! The students expanded the inflatable material library to sugar, chocolate, ice cream, and mozzarella cheese.

Left: Reception attendees enjoy the students’ unique creations. Right: Class instructors Chin-Yi Cheng, Wen Wang, Jifei Ou, and Lining Yao explain Inflated Appetite. Photo credit: John Werner.

We had the the idea of hosting a final reception while we were designing the class. It was meant not only to showcase the students’ outcomes throughout the class, but also as a statement of our attitude towards food design and to let people actually enjoy food and creativity. With support from MIT-SUTD collaboration office and the Media Lab’s Advancing Wellbeing special interest group, we created a three-part reception: food design gallery, food and drink for serving, and food for demo.

Since it was a “reception,” the second part was food and drink for serving. Our goal was that all the food and drink we served needed to be related to the topic of the class, and re-designed. We tried to show how unusual tools, such as a robotic cutter and a liquid nitrogen tank, can bring unusual experiences and flavors in the the kitchen. We had pizza cut with a robot arm, liquid nitrogen-made drinks, and inflated crackers, among others.

The last part of the reception, you might say the central part, was the live demos from four groups of students. They learned the basic techniques, innovated on top of those techniques, created their own dishes, and cooked in live demonstrations. We are very proud of them for being so active and passionate! We hope they bring home a new recipe, a good memory of being a creative high-tech chef for a night, and confidence from conquering the world of material design with their knowledge and creativity.

The food we eat every day has gone through a series of procedures before it ever reaches our stomachs. From the beginning of planting, fertilizing, harvesting, to transporting, distributing, and cooking, each procedure involves numerous engineering works and scientific knowledge, and each has contributed to the final quality of the food. We hope this class may help a bigger audience to envision what the future of food, cooking, and the kitchen might look like, and how experts from different backgrounds could add new intellectual ingredients to the future of food. As researchers at MIT, we are immersed in different technologies and their typical applications. If we all start to think about how math, computer science, material engineering, synthetic biology, digital fabrication, and human-computer interaction could be embodied and democratized in everyone’s kitchen, our perception of food would be dramatically altered.

As we are very much interested in hacking material properties and material fabrication, we consider food materials as a long-term research direction. It involves so many types of scientific knowledge and engineering efforts to redesign our cooking and dining experiences. One thing we would like to pursue next is to integrate the tools and processes of digital fabrication into the kitchen, so we can create food that exhibits new properties and flavors. For example, can we create one piece of brownie that gradually changes its flavor from one to another? Can we embed edible light guides in food for display? To achieve any of this, we need to learn more about not only the material science, biology, and chemistry, but also how this would change the way we cook and eat.

Lining Yao and Jifei Ou are material and interaction designers and fabricators and PhD students in the MIT Media Lab’s Tangible Media group.