Chemistry AND Cooking with Christophe Lavelle

Ilham Kadri: Hello everyone I’m truly delighted to be in this lovely kitchen studio with Christophe Lavelle, who is one of the foremost experts on the chemistry of cooking, or molecular gastronomy, and the relationship between art and science. 

Christophe is a biophysicist and an epigeneticist. He is a researcher at the Centre national de la recherche scientifique (CNRS), co-founder of the Food 2.0 LAB and runs a lab at the National Museum of Natural History in Paris. His research focuses on the regulation of gene expression and the biophysical properties of macromolecules… including the ones you eat! 

He teaches in many universities and establishments throughout Paris including the famous Le Cordon Bleu. So let's get started. Christophe, welcome. Really so proud and thrilled to have you here, Christophe. So tell me, Christophe, you are French I believe. So how come a PhD, a teacher, a worker, you are employed by the CNRS, which is one of the research centers in France and beyond, can do cooking.

Christophe Lavelle: First, because at the CNRS we like to study everything, which means we have people working on sociology, history and physics, chemistry and biology. And cooking is indeed gathering all the knowledge because when you cook, you have to understand about the history, where the recipes come from, about the geography, about the chemistry. Of course. Because lots of chemical reactions happen. And since I loved cooking and I loved science. I decided just to merge. 

Why chemistry AND cooking? 

Ilham Kadri: And this is why you are here, because you know the podcast is about AND is the future. So the A-N-D and we are putting things which can seem in opposition, but people like you, heroes, right, they really put those two together. So tell me, you wake up one day and just say, I'm gonna do, go from chemistry to cooking and I'm gonna do it as a job now.
Christophe Lavelle: Something like this. Yes. I started like, I wanted to do science and because science opens your understanding of everything around you. And I also wanted to cook and I said, so the best way to do science and to cook is to study the science of cooking. So I'm happy every day because every day I'm cooking and I'm doing science, so that's perfect.

Ilham Kadri: And you did it after your PhD?

Christophe Lavelle: And I did it after my PhD because the trouble is if you want to get a position in the CNRS, which is very selective, cooking is not considered as a serious subject. I mean it's something you do at home. And so I entered the CNRS because I studied the epigenetics, research connection with the food you eat and this is something serious but then I had to convince people at the CNRS that indeed cooking is also something very serious because when you cook, you eat differently. And if you eat differently, it has an impact on your health and the environment and many things.

What is molecular gastronomy? 

Ilham Kadri: So this is delightful because, you know, being French - Moroccan. I grew up in Morocco, so obviously we had, you know, the delicacy of cuisine and tagine and couscous. But French cuisine is also very well known. I love the Japanese cuisine. I'm putting my apron today just for showing off, but, you know, you are the master today. So tell me about these, you know, molecular gastronomy. Again, two things which seem in opposition, but it's about the molecular, which the chemist I am, we know about it at Solvay we use atoms and molecules to produce our products, and gastronomy, which, you know, it's your art. So how you combine both? 

Christophe Lavelle: Gastronomy is both art and science. Indeed. gastronomy was defined the first time by Jean Anthelme Brillat-Savarin. Brillat-Savarin is quite famous because we have the cheese, but it was a guy before. He lived two centuries ago. He wrote Physiologie du Goût, a very, very famous book. And this is in this book published in 1825 that was defined for the first time the word gastronomy in front in French. So gastronomy is the knowledge and understanding of all that relates to man as he eats. So which means, as I said, if you really want to understand what you eat, you need to understand. And Brillat-Savarin said it is about chemistry. It is about natural history (doesn't talk about biology at that time). And physics. And so molecular astronomy is just the understanding at the molecular level of all that relates to man as he eats. That's just a question of scale. Like you have the biology. And with the microscope and atomic force microscope and electronic microscope, you have the molecular biology.  That's exactly what we are doing here.

Ilham Kadri: But you bring more creativity and ingenuity like we do in our labs with polymers, right. The sky's the limit.

Christophe Lavelle:Because the fact is when you do the science, you understand things. And when you understand things, it might provide some ideas to invent new recipes, to try new things. And that's how molecular cooking arises. Because, it started with the science and then you have many chefs saying "oh, this is interesting, what scientists are doing". And they start to do weird things like with liquid nitrogen, alginate, and people start to call it molecular cuisine or molecular cooking. Just to remind that this is about art. This is cuisine. But you have this scientific spirit, which is in the molecular world.

Ilham Kadri: So it's a real science because when I, I mean the first time I was exposed to those molecular gastronomy, you have those fumes. But it looks like showing off. But it's more than that.

Christophe Lavelle: It can be a part of the show. And that's usually what people know about molecular cooking is this kind of spectacular things. But I would say to my mind, molecular astronomy is 99% only just understanding something very classical like you do you make a mayonnaise, you make a chocolate mousse. This is molecular astronomy. If you really want to understand and make it perfectly and know why. You have to put the chocolate slowly with the egg white whipped and why you should or not add some salt in the egg white. And everything is not spectacular at all, but this is real molecular gastronomy. 

Inspiration to start cooking and role models

Ilham Kadri: Wow. Wow. But, but tell me at home now, going a bit more personal when you grew up right. Was your dad, your mom, your, your parents, your family cooking? Were you in the kitchen at all?

Christophe Lavelle: Mostly my mom, but uh, as a kid I used to cook. Yes. I already loved it.

Ilham Kadri: So it started there not only at, in the Lab of CNRS?
Christophe Lavelle: No, it started before, mostly with cakes. Like kids usually like sugar also, I cooked pastry. But then when I grow up I started to cook more seriously in many different things.

Ilham Kadri: So you have restaurants in mind or chefs you know, who are role models in molecular cooking?

Christophe Lavelle: Not specifically. I mean, you have many many chefs. Not in France Indeed, but Spain is very famous. I had a very, very good experience in San Sebastian. And I used to teach at Basque Culinary Center, which is partner of this restaurant. And it was really, very amazing. And it was very clever, I would say. 

Ilham Kadri: And you were in Dubai, you say? 

Christophe Lavelle: Yes, alsoI mean I used to travel. I'm lucky for that. And each time I go somewhere I try to find a specific restaurant where there is something to say. So it can be a very traditional restaurant or I would say the opposite. Something very fancy that just exists at that place. And you want to be impressed and sometimes you are impressed, sometimes you're all disappointed, but that's the way. 

Teaching

Ilham Kadri: And in Paris, I'm curious, do you have students coming to your class and classroom just to study this and how long does it take?

Christophe Lavelle: Basically, I have two kinds of students. I have students from medical schools and want to become doctors. And I teach them very serious things about the food and the health and cancer and things like that. And I have cooking students. Indeed students who wants to become cooking teachers. So there are teachers that are still studying to become, cooking teachers. And that's, most of my courses are in the kitchen because it's just to tell chef how to become teachers, and for all this, most of them already know perfectly how to cook, but they don't understand everything. And as teachers, they need to understand, in order to better teach. So they make perfect stew, perfect soufflé  but they don't know why. Just because they used to. And it's fine. 

Ilham Kadri: They have a recipe in mind and they follow the methodology

Christophe Lavelle: It's not easy because if the student is failing, there is something they cannot explain. So I just explain to them, you know, if the soufflé is working, it's because that, that that and that. 

Demo: making caramel with bicarbonate of soda and liquid nitrogen

Ilham Kadri: I love it. I love it. So, Christophe, let's start now cooking, right? And having some fun cooking. You know, we are celebrating our 160th anniversary at Solvay. So very proud of this long-lasting history. And we have some products which are going to recipes, right? So as a chemist, but a good eater as well, I love that. One is called Natural Vanillin, which is actually a very sustainable product. We make it actually from waste from a rice husk which normally we throw. We collect that and we bio-ferment the product we extract and does go to natural Vanillin which replaces vanilla which comes from the orchids from Madagascar. Very rare, expensive, not sustainable to transport. So we like to say that we replace, you know, vanilla in your chocolates, cakes, but in a much more sustainable way. 

Christophe Lavelle: Yes. And vanilla is something very special from a physiological point of view. Everyone loves Vanilla. And we don't know why. Because there is something in the brain that makes us, every culture loves vanilla and this is a pure mystery and we don't know why.

Ilham Kadri: Neuroscience PhD, that's your next, next round. But the other product is bicar, we call it sodium bicarbonate, which my grandma used to use in Morocco, right. So it's products, which is there since 1890s. Right. And now it's byproducts, which are highly in demand, not only used by the way in cooking, but also, you know, depolluting air, cleaning air, et cetera. So it has industrial uses and I'm sure we're gonna tell us a lot about bicar and its impacts on health.

Christophe Lavelle: Yes. We will use it for a recipe. And indeed you find bicarbonate in many, many different recipes because it has two main roles. First, it helps to control the pH. So if you have something too acidic, adda little bicarbonate. And that's also why it's good for your digestion because it can regulate the pH. And some people take the carbonate when they have problem with stomach like this. So it's good for this. And we can see the reaction. Indeed. This is very, uh, we always have to do experiments. 

Ilham Kadri: Yeah. Let's do that. So a lemon. 

Christophe Lavelle: So the very, very, usual thing you want to try is just to put some lemon in the glass, which is something about pH two or three. So really acidic. And I got my spoon. And what happened? This is bicarbonate here. Just put it here. What happened if you put some bicarbonate in the lemon. You trigger a chemical reaction. And in this, you just… it illustrates the two advantages of using bicarbonate is first it kills the acidity. So it might be good for different reasons. But at the same time you have this reaction that creates foaming. This is carbon dioxide. And the good thing is, If you use it in the kitchen, you can make foam in the kitchen. And that's indeed, what people do when they put bicarbonate in cakes, it is just to have a kind of… like yeast, but not biological. Chemical yeast. And it does the same job. Because it just creates bubbles and you have your cakes just getting this huge volume. So we won't cook any cake here because I wanted to show you something very quick. Cake for next time. So we will just make a caramel. But a special caramel; it has to be special. So to do a special caramel, I just use normal sugar. There is no magic in the sugar.

Ilham Kadri: Because there is a normal sugar as well?

Christophe Lavelle: You can use many sweeteners

Ilham Kadri: This is traditional sugar. 

Christophe Lavelle: Yes. This is saccharose, or sucrose, so about 150 grams. And sorry, I just need to clean my spoon. 

Ilham Kadri: So 250… 

Christophe Lavelle: 150, and I will put about… I also need to put some lemon and, um, well, I will put it directly here. It's about half lemon, which will do something like 15 grams, I would say.

Ilham Kadri: No reaction here, right? 

Christophe Lavelle: No reaction here because just lemon and sugar, maybe I would use a little more because I like acidity. And this is a small Lemon; of course, in the kitchen I'm supposed to use the balance for everything here, you know, is just to show the principle, the idea, and maybe just a little water to help like this. Just like this. Okay. And now? Let's go with this, temperature maximum. We want to be very quick. Because what happened here is a very classical chemical reaction, which first hydrolysis the sugar, broken down into glucose and fructose. And after hydrolysis, you start to have caramelization reaction. And you create hundreds of different molecules that provides all the flavor, the color of the caramel and the taste because you are lowering the sugar 

Ilham Kadri: but did the decomposition into smaller molecular happens at room temperature.

Christophe Lavelle: It's with heating. I mean hydrolysis happen at room temperature. Yes. But then when you eat, you accelerate hydrolysis and then you start to have browning. And browning for the sugar. For this sucrose it's about 150-160 degrees. Okay. And you have to be very careful because when it starts, you go very quickly from a nice brown caramel to a ugly caramel and you missed it.

Ilham Kadri: Yes. That's what's happened to me often, it is very black.

Christophe Lavelle: Usually in the kitchen, you have to have to be careful. You have to watch. So as long as there is still water, we are free to,do what we want because it won't go above 100 degrees, I would say. But once the water disappears, then you start to… you want to be very careful and meanwhile when this caramel is cooking. we will put it in liquid nitrogen. Because usually when the caramel is done, it's very hot. You have to pull it on a plate and wait for one hour in order to be able to break it and eat it. We don't have one hour now. So we'll just put it in liquid nitrogen and in a few seconds we can…

Ilham Kadri: can we get liquid nitrogen at home? Because that looks very, you know, at home. Highly sophisticated

Christophe Lavelle: Here, we have a special home, I would say. So we just came with this nitrogen that's here. I can put it here. And anyway, at the same times, you know, I have to check my caramel, I have to put on my glasses because we are supposed, when we manipulate liquid nitrogen, to be careful….

Ilham Kadri: it’s chemistry, so safety first 

Christophe Lavelle: the caramel is almost done. So I just take it out.

Ilham Kadri: I'll be a bit away. I don't have glasses.

Christophe Lavelle: Oops. Sorry. I just pour the liquid nitrogen here. 

Ilham Kadri: so that we know it's very spectacular. 

Christophe Lavelle: We have to be careful because it's minus200 degrees. And this is the caramel. And I put bicarbonate in order to get a foamy caramel. Here is a foam.

Ilham Kadri: Amazing.

Christophe Lavelle: And I put the foam in liquid nitrogen. I froze my 160 degrees caramel into a minus 200 degrees liquid nitrogen. So this is really quick.

Ilham Kadri: Here when magic, you know, embraces science

Christophe Lavelle: and now that's done. So I don't need my glasses. And we just wait.

Ilham Kadri: So do you often use liquid nitrogen in your recipes or…

Christophe Lavelle: not at home, no. But in the restaurant, yes.

Ilham Kadri: And is it always to go quicker, right? In freezing 

Christophe Lavelle: Mainly, you have to use it, in front of the customers because it's for the show. If you just do this in the kitchen, this is not that useful. And usually you do sorbet, like at La Tour d'Argent in Paris, a very nice and famous restaurant, they used to have a marvelous dessert, Philippe Labbé was the chef at that time, and they make at the same time a "crêpe flambée" and an ice cream with the liquid nitrogen, so very cold versus very hot, and then they served the customers and it was a marvelous dessert

Ilham Kadri: Look at that!.. 

Christophe Lavelle: So this is caramel foam. Lots of bubbles. And we will be able to eat. So I break it because we want to have small pieces, that's it. Only sugar, lemon, and bicarbonate. And the good thing with bicarbonate we'll fill it. It's a little salty because you have the sodium. 

Ilham Kadri: Yeah, indeed. How much bicar you put there? I didn't, watch you good enough?

Christophe Lavelle: about three gram. Three gram like this. Because if you put too much, it is a huge foam, but then you feel it in the mouth.

Ilham Kadri: Yeah. So you said two 250, right? Sugar. And?

Christophe Lavelle: about 150 grams. About 15 -so 10%- of lemon, for the acidity and for the reaction. Little amount of water. I don't know exactly how much. And,let's say 3 grams of bicar. And, I don't want to break this stuff, but, well, maybe we can just, just show how it is. Yes.

Ilham Kadri: Wow. Look at that.

Christophe Lavelle: youcan already try like this.

Ilham Kadri: Yeah. It's really nice. Thank you.

Christophe Lavelle: It's very cold.

Ilham Kadri: Mm-hmm, wonderful. And, and crispy.

Christophe Lavelle: And, crispy. Yes.

Ilham Kadri:  That's great.  We're gonna give some to the crew, by the way, for everybody to the kids as well. So this shows that, at the end of the day, cooking is more than an art. There is science behind it. And what you say which is fabulous, is more you understand the science behind it more you can actually not only perfect your recipes, but actually do better things for the health. 

Christophe Lavelle: You can do better things for the health, better thing for the environment, better thing as taste, because indeed, again, Brillat-Savarin, when he talked about gastronomy , at the end, he said that it's also about cooking, which is the art of making things palatable. Which means this is really the idea of… it has to be good. That's the first goal. It has to be good. And if it is good, you want to eat it. And then it's better if it is also good for your health and good for the environment. But if the taste is not good. There is no use to, to work on a dish. So you really need to understand all the reaction and what happens in the brain and what happens with the sugar, with, proteins and with everything.

Favorite recipes and foods 

Ilham Kadri: So what's the best recipe you like to cook or to eat and or to eat? 

Christophe Lavelle: It's hard to say. When I started to cook, what I liked in cooking is to start from raw ingredients, which means mainly vegetables, but also fish. For animals like mammals, it's a bit harder because you need someone to kill it and to prepare it. AndI really like the idea to just catch real, full ingredients. And prepare it from the beginning. So usually I'm cooking vegetables and fish and I mean, sometimes a little piece of meat. But, and then you have all the creativity you can think about. When you are traveling, you have new ideas. When you read  books about the history of cooking you have new ideas. When you meet chefs, you have new ideas and, and then you provide the students. And I try to give this new ideas to my students. And make them think about new dish. And usually I told them, you know, try something new, and you will fail. That's fine. Failing is good. Failing is good, but you have to understand why. 

Ilham Kadri: You learn. Yeah, exactly. And you don't repeat your mistakes. We love it. That's part of our values at Solvay. So help me, I mean, you need good ingredients to, you know, like anything else I guess, you know, good veggies, good fish farming can be also a bit, you know, here and there. So I guess you look at the quality of your ingredients and then I'm interested by the spices. In Morocco we are using a lot of spices and et cetera. So what's the role there in a good molecular gastronomy?

Christophe Lavelle: So, of course, with good ingredients I would say it's better, but it's also easier. So usually what I say to other students and to the chefs is, having good ingredients and doing something good with them is a kind of responsibility. But also having bad ingredients and succeeding in doing something good is also a good thing and a challenge. And it's interesting because you have lots of kind of waste or things that people don't want to eat or let's say I got a kilo of tomato and I try and it's not good tomato, but I have to use it. And to use it, I have to think about the best way to make something good with bad tomatoes. And I will make a sauce and I will add some spices and thanks to the glutamate you have in the tomato, you have umami taste. And at the end the sauce will be perfect.

Ilham Kadri: So finish the experiments. Show us. Wow. That's it. Can I try one?

Christophe Lavelle: "bon appétit"…

Ilham Kadri:  Bon appétit. Magic.

Christophe Lavelle: Just imagine on a cake, on a custard, and we have to put it on something. 

Advice to young scientists and chefs

Ilham Kadri: So tell us now you know that the podcast is delivered to our audience. So is this, Solvay chemists, researchers, employees around the world, but also to the youth. Right. So what would be your best advice to young scientists and young chefs?

Christophe Lavelle: The same advice. I would say the first thing is always to keep open-minded, which means you have to be curious about everything. Curiosity is probably the most important quality for a chef and for a scientist. And also, this sounds obvious, but you have to like what you are doing, you have to enjoy.  Because if you enjoy it, you will do it. I mean, you have a good chance to make good things and to be good at what you are doing if you really enjoy it. Of course, when you are doing science or professional cooking, basically you work 15 hours per day minimum and if you don’t enjoy it that's a disaster. Don't do that. So, you have to have this passion, otherwise do something else.

Ilham Kadri: Yeah. And you said earlier failing is okay. You know, you learn from it. Right. Learn and unlearn and relearn

Christophe Lavelle: And I would say in science, failing means you probably improve. Because if you don't fail, you don't learn anything. It's something obvious. Okay, I want to do this. I think it will make this, and it's exactly what's happening. So I don't learn anything.

Ilham Kadri: So…  and you eliminate  one path because you fail, so you are gonna do something else. So that's science.

Christophe Lavelle: You have to fail. And you have to take risks. Otherwise, if you don't take risk in the kitchen, you do something that everybody is doing. And if you take some risk you might do something different. 

Love of music

Ilham Kadri: So someone told me that music plays a big part of, you know, in your life and even you played piano at the beginning. 

Christophe Lavelle: I used to play, I started to, not professionally, but earn money by playing piano in the club. Yes. In Paris. And Tours, in the Loire Valley, a small city where I used to live. Unfortunately, I mean, science, cooking… You cannot do everything.

Ilham Kadri: You have your plate full already. 

Christophe Lavelle: And if you want to try to be good at something, you cannot do everything you have to choose.

Ilham Kadri: But you listen to music. 

Christophe Lavelle: I'm listening a lot of music and get some inspiration from music. And the fact is it's all about emotion. Listening to music, playing music, cooking. You do it just because you want to create some emotion for you. And for the others. So that's a bit the same music and cooking.

Ilham Kadri: So next time you didn't know this, but we will have a podcast with a pianist and a chemist, so it's fun as well. So that's perfect. Well, Christophe, thank you. I think you gave us a great gift today. A gift showing that, the future is the present. And the real presence between science and art, between cooking and chemistry, including molecular gastronomy. And frankly, your generosity as a human being, as a scientist, as a professor, a teacher, a traveler is a real inspiration for all of us and for me. I'm getting away, you know, wanting to be in the kitchen.

Christophe Lavelle: I'm sure you are cooking. 

Ilham Kadri: No, not, not at all. My husband would tell you she's not really, but I'm a good eater. I loved to cook when I was younger in Morocco. But today, you know, having a chef like you, you know, just watch and enjoy and taste. So thank you. Thank you for this beautiful gift. Thank you very much.