Science in the Kitchen: Harvard's Emulsions and Diffusion Course with Ferran Adria

Overview

This video presents a science class at Harvard themed around science and cooking, where chefs collaborate to engage non scientists through hands‑on labs and cookery demonstrations. Ferran Adria, hailed as one of the world’s top chefs, visits to help kick off a course that blends culinary practice with physics and chemistry concepts.

• Key approach: cooking as a doorway to physics and chemistry, not just a kitchen skill.
• Equation of the week: a weekly physics equation is introduced and celebrated with student participation.
• Public reach: thousands attend lectures and millions view the content on YouTube.
• Signature demonstrations: emulsions, basil oil and aioli, molten chocolate cake illustrating diffusion and diffusion dynamics.

Introduction and origin

The video documents a science class at Harvard that is deliberately themed around science and cooking. The host physicist explains that the class was born from a desire to reengage non scientists in physics by connecting it to everyday, delicious experiences. A pivotal moment comes when a collaborator from Barcelona, Jose Campos, suggests inviting Ferran Adria, widely considered the best chef in the world. The invitation is accepted, and Adria agrees to come to Harvard to discuss science in the context of cooking. The public response is immediate and intense, with signs and media covering the event long before social media fully dominated such outreach. The class evolves into a formal course that continues to attract broad interest, including public lectures that reach tens of thousands of people over the years.

Course model and traditions

The class is designed to be accessible to non scientists, but it remains a rigorous science course. A core feature is the equation of the week, which the instructor presents with a call for audience applause to emphasize engagement and demonstrate that physics can be an approachable language for everyone. The course relies on bringing in world-renowned chefs to explain culinary science, focusing on topics such as foams, emulsions, and the physical properties of emulsions like elasticity. Over time, the program builds traditions and materials around these demonstrations, including a weekly recipe and a lab setup that blends cooking equipment with scientific instruments.

Labs, recipes and demonstrations

Among the demonstrations is an aioli made from basil oil, where the basil’s chlorophyll is preserved while extracting fragrance. The process begins with heating oil just below its smoke point to extract basil flavors without burning them, followed by blending the infused oil with egg white and an emulsifier (lecithin from the yolk or mustard) to form a stable, vibrant green mayonnaise. The liquid emulsion, initially two immiscible liquids, becomes a solid-like structure due to droplet interactions, surface tension, and the volume fraction of dispersed droplets. The demonstration is used to explain how elasticity arises in emulsions when the droplets are forced to pack together and deform, a phenomenon captured by a simple equation linking surface tension, drop size, and volume fraction.

Diffusion, diffusion equation and food science

The course uses molten chocolate cake as another signature recipe to illustrate diffusion in a culinary context. The inside of the cake remains molten depending on heat diffusion, allowing discussion of the diffusion equation in a tangible setting. The instructor recounts how a history major used diffusion theory to scale a lasagna recipe at Thanksgiving, showing the real-world reach of the concept beyond physics classrooms. A book was written about these ideas and became a best seller on Amazon, underscoring the broader cultural impact of framing cooking as science.

Public lectures and reach

In addition to the Harvard class, public lectures feature chefs who travel from around the globe to share demonstrations. The program has drawn more than 45,000 attendees to lectures and has amassed millions of online views on YouTube, with global audiences including a large Chinese viewing audience. The shift toward including a YouTube chef as a recurring presenter reflects a strategy to broaden the platform and reach younger, digitally native audiences. The program culminates in a moment of reflection about the future of science communication and the role of culinary experts in making physics accessible to a broad public.

Conclusion

The video ends with an appreciation of the collaboration between physicists and chefs and hints at ongoing expansion, with plans to continue pairing culinary artistry with physics education to engage diverse audiences and demonstrate the science behind everyday cooking.