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Food Science

Movers And Shakers

This cookbook showcases flavor and chemical structures

Arielle Johnson talks to C&EN about her new book, Flavorama

by Chris Gorski
May 24, 2024 | A version of this story appeared in Volume 102, Issue 16


Arielle Johnson, wearing two black shirts layered on top of each other.
Credit: Courtesy of Arielle Johnson
Arielle Johnson earned a PhD in agricultural and environmental chemistry at the University of California, Davis. She has collaborated with renowned chefs and has been published in academic journals, magazines, and newspapers.

Books about food often feature pretty, mouthwatering pictures of delicious dishes, not diagrams of chemical structures. But Arielle Johnson’s Flavorama is less like a cookbook and more like an instruction manual about building flavor according to first principles. It features cooking techniques, a set of scientific laws of flavor, and playful, insightful drawings of the molecules involved in transforming food from mere nutritional necessity to something satisfying and even indulgent.


Education: BS in chemistry, New York University; PhD in Agricultural and Environmental chemistry, University of California, Davis

Favorite flavor molecule: 2-acetyl-pyrroline. In basmati rice, pandan, and tortillas, it smells very pleasant and nutty. But when it shows up in wine, it smells like a mouse.

Bigger challenge, writing a book or a journal paper? I found the book very challenging to write. Once you master the academic voice, I find writing a journal article pretty straightforward, because the structure is already determined.

How’d you develop your drawing style? As a graduate student giving talks, the clip-art aesthetic was not for me. I had to go DIY.

Johnson is a PhD chemist and food scientist who has worked on TV programs, written for newspapers and magazines, and collaborated with renowned chefs around the world. This book combines her scientific experience and insights with visual and verbal metaphors to effectively communicate the complex sensations that are flavor.

Johnson cites encountering Harold McGee’s book On Food and Cooking when she was a student as a formative experience. “That’s obviously the classic work on cooking and cuisine and science,” she says. Johnson says the book, along with a New York Times Magazine article that featured the pioneering Spanish chef Ferran Adrià, inspired her to bring together her interests in science and food. “There are food science programs, but there’s not really any kind of formal education combining lab science and chemistry with cuisine.”

C&EN’s Chris Gorski spoke with Johnson about her book, the colorful illustrations in it, and the ways that science and creativity help explore and understand how we experience flavor. Their conversation has been edited for length and clarity.

What was the project that first brought together your interests in chemistry, cooking, and food?

Structure of 2-acetyl-1-pyrroline.

One of my chemistry professors at New York University, Kent Kirshenbaum, happened to be a big food nerd. While I was taking an organic chemistry lab with him, he had very serendipitously started a group called the Experimental Cuisine Collective. I sort of talked my way into the first meeting and stood at the back. Then I asked/begged/insisted on doing my senior thesis research with the group. So we ended up using polymer chemistry–informed approaches to making different versions of a Turkish stretchy ice cream, dondurma.

Instead of being made with a custard with eggs and cream—the way you would make an American- or French-style ice cream—it’s got milk and sugar and flour ground from the root of the salep orchid. The orchid’s primary carbohydrate is a soluble fiber called glucomannan, so it’s like long chains of glucose and mannose. Once you make it into ice cream, it has this taffy-like, stretchable structure. The orchids are wild. They grow in Turkey, they’re endangered, they’re difficult to export. Alternative recipes for this ice cream called for starches, and it didn’t really achieve the same flavor. We looked specifically for ingredients that had the same type of glucomannan and we found konjac flour, which is a Japanese thickener from the konjac plant. We figured out how to use this alternative polysaccharide product to make an ice cream that had a stretchy texture without using these endangered ingredients.

How would you compare working with chefs to working with scientists?

It definitely took a little while to find the right rapport to work with people. At most restaurants, you don’t have time to think a lot about how or why something works and then do something totally new with it. Your job is to become very skilled at executing something difficult at a very high level over and over again. Thinking about it in a kind of abstract way is often not useful. The chefs that I started working with tended to be the ones who wanted to do new things or had an unusual curiosity about how and why things work.

I don’t like to take a position of like, well, I am a learned and important scientist who was deigning to come into your kitchen and then I’m going to tell you what to do. Because that’s just really condescending. The cooks and chefs I work with have amazing intuition and experience-based knowledge about a lot of the same things that I think about but parallel to how I think about them in a molecular way.

Image contains hand-drawn structures of five sugars, arranged from least sweet to sweetest: lactose, maltose, glucose, sucrose, and fructose.
Credit: Illustration by Arielle Johnson, courtesy of Harvest, an imprint of HarperCollins
Flavorama contains many hand-drawn images which feature chemical structures, foods, and maps of the relationships between ingredients and flavors.

What makes flavor such a fascinating subject for you?

One of the things that attracts me to flavor, just as a scientific discipline, is that you can’t approach it as just a chemist. You have to feed food to somebody and record what they are experiencing. It is inherently an interdisciplinary, multidisciplinary practice. The number of different fields that have something to say about flavor is really fascinating. You basically have to use the same kind of statistical tools that you use in econometrics—but for understanding the flavor of chocolate or wine.

Why did you frame your book around what you call laws of flavor?

Cover of the book Flavorama, written by Arielle Johnson. The background of the cover is yellow and the letters of the title appear in blue, red, and green, with the subtitle "A guide to unlocking the art and science of flavor" in black. Included are the author's name and that of Rene Redzepi, who wrote the forward.
Credit: Courtesy of Harvest, an imprint of HarperCollins
Flavorama, written by flavor chemist Arielle Johnson, details the science behind flavor.

No one can tell you from a list of molecules exactly what something is going to taste like. But we do know that flavor is molecules; flavor is always going to come from molecules.

So we’re dealing with material reality, and the first rule of flavor is that it is taste and smell. We use both of them to create our composite sensation of flavor. Most people understand that taste is part of flavor, but the smell thing tends to throw them for a loop. It doesn’t feel like it’s smell, but flavor is not only stuff that’s happening on your tongue—it’s also things that are happening with volatiles.

The second law is that flavor follows predictable patterns. This was probably the most artistic of the laws. But my observation was that professional chefs who were thinking about flavor very deeply and creating new recipes and techniques with it try to improve their mental models of cooking by looking for patterns.

So the third law is that flavor can be concentrated, extracted, and infused. There are lots of techniques where you are moving flavor molecules around selectively. And that can mean anything from drying out a piece of fruit by removing water and therefore concentrating all the other flavors or juicing the same fruit, removing the solids. But it’s also things like making a cup of coffee is selectively moving flavor molecules from inside the coffee bean to hot water. And stock is similar. Once you get into different solvents like vinegar and sucrose solutions and fats, you have a whole other set of ways that you can be selective about how these things move around.

And then the last law is that flavor can be created and transformed. Because flavors are molecules, they have chemical reactions. So if you know the basic set of those reactions, you can quickly understand what is happening. That’s generally through the application of heat or biochemically through fermentation. So, yeah, I’m a chemist, and we think about mechanism a lot.

When somebody picks up your book, what do you want them to take away from it?

At the most basic level, I hope they take away an idea that there is something going on under the hood with flavor and that it’s not that difficult to know a little bit about it. And knowing a little bit about it, even if you’re just cooking in the most basic way, will make you a much more confident, happier, and delicious cook.


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