StarTalk Radio - The Science of Flavor with Arielle Johnson

Episode Date: July 12, 2024

What is flavor? Neil deGrasse Tyson and co-hosts Chuck Nice and Gary O’Reilly explore the science of what makes some foods tastier than others, what is “umami,” and how flavor changed in the 20th century with food scientist Arielle Johnson.NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here:https://startalkmedia.com/show/the-science-of-flavor-with-arielle-johnson/Thanks to our Patrons Lisa Pulkrabek, David Guilbault, TheRealErikEvans, Daniel Jones, Joshua Troke, Chris Hampton, Shaun Grossman, Pete Evans, Chris Love, and andrea nasi for supporting us this week. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Chuck, I don't know if that episode made me more hungry or less hungry. I think if we're talking about stinky herrings and less hungry, I'm going with less hungry. You're going with less. Yeah. That was like so many elements and aspects of food that I hadn't even imagined. And we just began to plumb the depths of it. Yeah. But here it is.

Flavorama all the way. Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk Special Edition. Got with me my usual co-host, Gary O'Reilly. Gary? Hi, Neil. Hey, hey, former soccer pro turned soccer announcer, and we get to share you with the soccer universe.

Thanks for being part of the StarTalk family. And of course, Chuck Knife, Chuckie Baby. Hey, what's happening? Gary, you and your producers put this together, so give me the setup for this. Okay, so I suppose we all do it. We all eat. Our bodies need fuel. We shovel it in and we burn it up. Into your pie hole. Yep. In their pie hole. Then it goes. But how many of us stop to consider the fundamentals of what we eat, such as flavor? Is it luck? Some meals taste better than others, or are we being cleverly led into a foodie heaven? Then ask yourself, why do some foods work better than

others? And whose idea was it to put sea salt on caramel? Really, whose idea was that? Because it works really, really well, but it wouldn't come straight to your mind unless somebody gave it to you. So then you go, is cooking just cooking or are we looking at science here? I'm going to guess it's always science. That's what I'm going to guess. That's all right, then. There's you out on a limb again, Neil. So we've got with us a repeat guest. This might be your third time on StarTalk, scattered over five or six years Ariel Johnson Ariel, welcome back to StarTalk

Thanks so much for having me back You have the coolest designation as a flavor scientist That's a thing Flavor It's a niche field, but yeah, we're passionate about it Okay, you are the flavor scientist That's how niche-y it is You're advisor to some of the world's top chefs, top restaurants.

You have a PhD from none other than UC Davis, which has a, I know about their wine division, but they also have a food division there? They do. I was actually in the wine department because they have a really strong experience with the science of flavor so so do i yeah that's that's anology isn't it that's yeah viticulture and enology yeah and you're co-founder of the fermentation lab which sounds a little weird you know that's better than the fomentation lab i I guess. And what does it have to do with that world renowned restaurant in Copenhagen

called Noma? So Noma started with, in retrospect, a little bit of a stupidly difficult creative constraint, which was let's cook with ingredients only from Scandinavia. Oh God. Which, yeah. And I mean, seriously, and we're celebrating this place. Come on. Potatoes, beets, onions. Let's yeah. And I mean, seriously, and we're celebrating this place? Come on.

Yeah, potatoes, beets, onions. Let's just get real. Cabbage. Cabbage, exactly. Exactly. This Noma restaurant is world famous, possibly even across the galaxy. And I know people, they are people with means, who said, this weekend, let's go eat out at Noma. And they chartered a plane and flew there just for that.

So this has got to have some remarkable draw upon people's taste buds. So what was your relationship with that restaurant? Remind us. Well, so when I was in grad school studying flavor chemistry, I went to grad school because I was really passionate about food and wanted to be a scientist that was working with chefs and restaurants and applying that. Noma was a place that had started their own Nordic food lab to study ingredients and flavor and were working with techniques like fermentation and wild ingredients and

just was sort of everything, you know, that I wanted to be doing. So I kind of talked my way into an internship in their initial lab and really hit it off with everybody. You just talked your way in? A little bit, yeah. Very cool. Yeah, I think they were a little skeptical, but after, you know, some light hazing,

a couple of cases of rhubarb to juice to see if I would do it. Yeah, no, it turns out that, you know, they're sort of deep thinking about flavor and how to find it and how to work with ingredients. And my knowledge of, you know, food chemistry was really complimentary. And you're also the science officer that even such a thing on Alton Brown's TV show, Good Eats. Yes, yeah.

Well, just to remind people, we had both of you on stage at the same time for a Star Talk Live at the, was it at the Beacon Theater? I think it was? The town hall here in Newtown. Okay. And it was some years ago, so we've been

exposed to you before. Does that relationship still exist? Good Eats isn't in production right now, but Allison was actually kind enough to come and do my initial book launch event here in New York at Rizzoli Bookstore. Is that the Flavorama book? That is the Flavorama book.

I have it. This is the book. Oh my God. I wrote it. That's cool. When did it come out? This came out in March. So it's been about three months.

March 2024. And subtitle, A Guide to Unlocking the Art and Science of Flavor. Can't argue with that. I mean, come on. Oh, yeah. Everybody loves flavor. Yeah, they do. They do.

Everybody loves flavor. Tell me, are you helping to create meals for a Michelin star restaurant so that they keep their star? Or did they not previously have a star? Until you arrived. It wasn't a kind of investment. They then earn one or more of their Michelin stars. We need another star. Go get Ariel.

Well, I don't think about things like Michelin stars, but it's the kind of thing where a place like Noma is constantly, you know, pushing the boundaries and trying to kind of not rest on the laurels and find ways of, you know of being more creative, coming up with new ideas. And it turns out science is really helpful for that. So I don't feel like I can take any credit for whatever awards or stars,

but I do know we work well together and make some tasty stuff. Are you just a kid in a chemistry, who just got a chemistry kit and you never let go of it? Is that what you are as a full grown-up? Yeah, it feels that way sometimes, definitely. Yeah, so, you know, I kind of do a mix of just playing. How much would you get to light on fire, right? This is the chemist's dream, right?

No, it's great, yeah, and, you know, fast reactions, slow reactions, all kinds of chemistry going on. So are there some fundamentals, Ariel, to your sort of view on flavor or actually the way flavor exists and how we experience it? Or is it as simple as salt? It often is, but not always. So, you know, going back, like, you know, we agree, everyone loves flavor. And they do. It turns out that everyone loves flavor, but no one really understands what it is or how it works. But fortunately, in the sciences, we do actually know that that information just hasn't crossed over.

Crossed over. I like that. Because the science of the rest of the world, has it crossed over? I don't know. But scientists are up on it. The walled academic garden um yeah so the the first things i like to get kind of bring people up to speed on is that flavor is molecules so you know everything that you uh experience as a flavor started as a molecule that binds with one of your many uh receptors flavor is an experience created

by your brain flavor is is mostly the senses of taste and smell, and those are our two chemical senses. So, whereas vision is sensing light and hearing senses pressure vibrations through the air. We call that sound, by the way. Yeah. But no, but that is what's, but is it sound until your brain interprets the signal into sound? Or is it just waves through the air? Yeah, philosophers like distracting themselves with that question. Yeah, yeah. So there's a difference here, real, is there not, between orthonasal olfaction and retronasal olfaction?

Yes. And I'm not quite sure I know the difference, but you will, won't you? Okay. Yeah, I do. Fortunately. So flavor is taste and smell. Most people understand that flavor is taste because all the flavor feels like taste. It's happening in your mouth. When I tell people that flavors also smell, and in fact, that smell is like probably a more larger part of flavor than taste. That's kind of a hard sell for people. I thought people knew that if you hold your nose, you don't taste your food.

We won't do that as an experiment. Some people know. Yeah, no, and it's a good experiment, especially now that more people have had COVID. I was going to say a better analogy is to have a cold. Exactly. Just think how you feel about food when you have a cold. And the reason is that normally you can't smell things and so food isn't nearly as appealing yeah so as like flat tasting as food is that is actually flavor

with only taste flavor without smell without smell tastes themselves are very flat um so yeah the the tricky way that smell is a part of flavor so first off uh while we're eating, our brain tricks us. It doesn't, we experience smell, but it doesn't feel like smell. It doesn't feel like it's happening in our nose. We'll be perceiving smells in our nose, but it's a pretty famous psychological illusion, actually, that sensation gets kind of moved so that you perceive it as happening inside your mouth. So if you, you know, were to take a jelly bean and chew on it with your nose closed like that, and then open your mouth, you'll feel like the kind of fruity flavors of the jelly bean bloom on your tongue. It's actually happening in your nose, but it's sort of translocated

in your brain to the mouth. The brain just never telling us the truth. The brain is always a liar. Yeah, yeah. Well, you know, I think it's important to know, you know, what's perception, what's reality, how are the two related? I mean, the other thing is when you say smell, most people think like sniffing. So like, oh, you have a plate of food and there's smells coming out of it. And I guess you sniff it before you chew it. I mean, you do. But yes, there's actually two types of smell, two types of olfaction, as Gary mentioned.

Sniffing is orthonasal olfaction. So it's, you know, ortho because it's normal forward, the front of the nose. But since your, you know, nasal passages in your throat is basically just a tube, air can go in through the nostrils, but air can also travel from, you know, your lungs out. And so while you're chewing your food, it's full of volatile molecules that are able to float through the air and they just sort of float up the back of your throat. Normally when we think of the word volatile, we think of something that would ignite into flames or a person who is otherwise unstable. But I think when a chemist used the term, they're just referring to molecules that will readily evaporate from wherever they were.

Yeah. So molecules that are kind of light and then sticky enough to be gaseous some of the time. But yeah, retronasal olfaction. Every time you have food in your mouth, every time you're chewing, every time you're swallowing, you get these little puffs of sort of scented air that go up the back of your throat and into your nose. And those volatile molecules can bind with your olfactory receptors and then you're smelling as you're chewing. Now, I was intrigued as a kid. I saw a map of the surface of the tongue and where, so here is sweet,

here is sour, salty, whatever. Was that just? Ah, that's BS. Come on, tell the truth. Unfortunately. That's gotta be BS. There we go. Yes, so unfortunately, the map is a fiction.

You don't have many taste buds in the center of your tongue. So the only thing I could conclude was that if I put flavors in the center of my tongue, I did not taste it. I found that to be so. Yeah, taste buds are like much more concentrated along the kind of edges and tip of the tongue.

Okay. Okay. So I wasn't entirely misled by it. No, no. But unfortunately, it's not quite as tidy as having the sour area. Yeah, because it was way tidier. I said evolution is not this tidy. It kind of makes sense when you look at the construction of your mouth and eating.

So along the edges is where you chew, and the first taste comes in through the front of your mouth. So that's the tip of your tongue. So it would make sense that that's where you would want to stimulate taste the most. I got a good one for you. I forgot what two cities I was between when I was giving public talks. And I had a driver and her name was Taylor. I think if I'm remembering that correctly. We had a whole chat about all kinds of things.

And she used to work for FedEx but then started Jindro trucks and that like like big trucks and now she became a driver like a car service driver so I had and she she knew I was a scientist we just started talking sciencey things and she said she made a discovery and I said and she told me the discovery was like, I'm going to try that. So here's her discovery. She eats her hamburgers upside down. You mean hanging upside down like a bat? No. I don't think that's what she meant. If you invert the hamburger and you bite it, all of the toppings you put on the pickle, the ketchup, the cheese, that hits your tongue sooner than it otherwise would if it were face up.

And it made sense to hear it, but then I tested it. It's like, yes, I don't have to keep swishing around the food to get to my tongue. See, I have a better way of doing that because this is how I do it. I just put all the condiments on both buns both sides both sides like the sauteed onions i put them on top and bottom everything you know innovation yeah yeah and now the only thing that i don't do is two slices of cheese top and bottom so maybe maybe i'll try that yeah that's not good. Hello, I'm Alexander Harvey, and I support StarTalk on Patreon.

This is StarTalk with Dr. Neil deGrasse Tyson. I'm just wondering a couple of things the big part of what you do I think this is what drives modern chefdom is not just what a flavor is but what a melange of flavors might be then what insights you might have in combining those flavors to come up with something transcendental. You know, a lot of restaurants now are much more like seasonally driven and are interested in, you know, things like local produce and things that peak and change with the seasons and figuring out the best way to kind of express the flavors of all those ingredients and put them together. I thought it was odd.

First time I ate at a Chinese restaurant and there were food items called sweet and sour or hot and sour, sweet and sour. And when I'm thinking to myself, do I really want sour with my sweet? And why are they putting something that burns my tongue in the middle of the honey? Why is there hot honey?

Like who's stuffed this stuff up? Well, I mean, it's interesting because Chinese cuisine is really like the oldest continuously developing cuisine. I mean, there's like recipes that are 6,000 years old that are from ancient China that are still good. Still good? Really? I mean, yeah, they're like

much more advanced than what people in Europe was cooking 6,000 years ago. I was going to say, they're still in use. It doesn't necessarily mean they're good. Thank you. Let's clarify that. So, Ariel, is there like a color wheel for flavors where, you know, when you're matching things that, you know what,

the sweet will go with the sour because it sort of lines up in the spectrum? I like that question. Yeah, like yes and no. Um, I mean, a lot of other flavor scientists have, um, spent time kind of building wheels like that.

There's, uh, the wine aroma wheel was, uh, one of the first ones. Yeah. Um, out of UC Davis.

Yeah. I mean, it's tricky because flavor is so multidimensional. Um, I mean, you know, color, depending on how you look at it has like three or four dimensions, um, or can be, you know, sort of expressed that way. I mean, like there's color, depending on how you look at it, has like three or four dimensions or can be sort of expressed that way.

I mean, like there's brightness, there's hue. Exactly. So, yeah. Or like cyan, magenta, yellow and black. There's like several different ways of expressing it. You know, with flavor, we have we have five tastes. Sweet, sour, salty, bitter, umami. Tell me about umami because none of us grew up with umami.

Umami just somebody just that just showed up at the doorstep. And then everyone goes, this has umami, this has umami. It's like, what the hell is umami? Umami is like the most recently identified of the tastes. You know, you can go back to like classical antiquity and find the Greeks writing about sweet and sour and salty and bitter. Umami, you know, chemically speaking speaking it's the taste of glutamate which is the ion form of uh glutamic acid one of the 20 amino acids that are in all of our proteins

it's a savory taste it's a kind of uh mouth-filling brothy savoriness didn't we just call that savory though like back in the day we just called that that savory. So did Umami bump out the word savory from the vocabulary? Well, yeah, I basically, you know, whoever like discovers something first gets to name it. So, you know, we had a concept of savory, but it wasn't until the early 20th century that a Japanese chemist, Dr. Kikone Ikeda at the University of Tokyo, he was studying seaweed broth. So in Japanese cuisine, they cook a lot with kelp called kombu. It's very, it's very Kikone Ikeda at the University of Tokyo. He was studying seaweed broths. So in Japanese cuisine, they cook a lot with kelp called kanbu. It's very savory tasting.

Is kelp the same as seaweed? I mean, are they considered the same food? Kelp is a type of seaweed. Okay. There are, you know, there are brown seaweeds, red seaweeds, various macro algae, things like that. But yeah, kelp is a particular type. So yeah, kanbu, it's actually like a very,

it's like one very long blade or leaf. We've all seen kelp forests. Yeah, exactly. I think it was even in Finding Nemo. So that meant it's really... It's legit. Yeah. It's legit.

So he was studying these broths and sort of concentrating them down and concentrating them down until he eventually like purified the savory component in them, which was glutamate. So he identified it as glutamate and then called the sensation of pure glutamate umami, which comes from umai and mi, which means delicious flavor, delicious taste in Japanese. So I thought it'd be something deeper than that. Oh, I thought it'd be something deeper than that. Yeah, so that was, you know, around the turn of the century, but it took about another 80 or 90 years to actually find the taste receptor for umami.

So there was some controversy throughout the 20th century of... As to whether it really existed. Is umami a real taste? Does it just enhance other tastes? What is it? But then, you know, we know what the umami receptor is. It's been well characterized. So it's kind of now officially enshrined as one of the basic tastes. Wow, that's fascinating. As you've discussed with us just now, you've mentioned the ancient Greeks, you've mentioned the Japanese. If you had the same plant, same protein in Japan,

would it have exactly the same flavor where in Eastern Europe around the Mediterranean? Or is this some way that's varied the flavors that come out of? Are you talking about a variation in the plant or a variation in regional taste buds? In the flavor itself, will the environment and then maybe the food chain that's involved, if it was a predator, would that change change i guess there's like two ways of looking this one um you know if if uh if you drink wine they talk about the concept of terroir which is

kind of uh you know sometimes it's described to just like the taste of the rocks and the soil which isn't really how it works but it is like the taste of place so um you know they have a lot of like clones of grapes there's like pinot noir clones that are genetically identical and uh if you grow it in the sonoma valley versus in you know new zealand they're going to taste different even though they're genetically identical so phenotype so you know the way the way that uh an organism you know appears in his constituent i'm going to add to that ariel she hung out at uc davis sure maybe they there's something about this i like like French wines more than I like Italian wines, but there was nothing greater than the taste of an Italian wine,

Tuscan Italian wine that I had in Italy, in Tuscany, on a ravine overlooking. I mean, just that wine. That was psychological, man. You were sitting there like, damn, I spent a lot of money to be here. This one better be worth it. psychological man you were sitting there like damn i spent a lot of money to be here basically the composition of any organism chemically biologically is going to be an interaction of its environment and its genes so growing the same plant or you know animal or whatever in two different locations will make it chemically different depending on how it responds

and then it'll taste different. Okay. If you had exactly the same fruit, two of the same fruit that you cloned, well, not cloned, but replicated, so they were chemically and biologically identical. At Star Trek, they used the replicator. Exactly, exactly. In two different locations. Two different people with different experiences

with food wouldn't necessarily have the same eating experience of them. We use our sense of flavor to kind of figure out what to eat to, you know, to not die, but also to, you know, fuel ourselves and, you know, hopefully increase our quality of life. So we use, you know, both taste and smell to help us with that. But we'll use like any context cues that we can find to figure out if this thing that I might be eating, is it a good idea or is it a bad idea? And so, you know, we're actually wired to kind of build up a bank of

those memories and experiences and kind of pull them up the next time we taste something and be like, okay, have I tasted this before? Did I have a good time? Did I have a bad time? Do any of you guys like root beer? Do you drink root beer? I used to. I was a kid. Gary, yeah. So, you know, root beer is a very American drink. It's got, yeah, kind of herbal flavors with some kind of wintergreen kind of stuff going on. Yes. In Europe, they don't really use those flavors for food. In fact, that kind of root beer-y scent flavor is most prominently used in bathroom cleaning products.

You know, and that's why we don't drink bleach here. You know, I mean, unless you're trying, unless you're listening to a certain former president who knows how to cure a certain kind of disease. Please don't do that. But yeah, no, I know. And I have European friends that have come to America and tried root beer and they're like,

this is absolutely disgusting. This tastes like a toilet. Like, why would you drink this? There's a an antiseptic ointment that tastes exactly like root beer which is like good to know tasting your ointment

no it smells smell is very much the case so you've experienced that you know aroma experience before but not in a food context it's in a very much not like a non-food context um so you know it's possible to like override that by exposing yourself repeatedly to to a new flavor in a in a food uh food way but uh without deliberately doing that people are going to have uh bring different experiences to their uh you know immediate surroundings and interpret flavor differently.

So cool. Okay, so now we all agree, I think, in spite of the raw food movement, that most of us like our food cooked. Not only does it change the texture, but flavors rise up in ways that were not there with the food remained uncooked. So when I think of heat, I think of breaking apart molecules, not bringing them together. So are there complex molecules in uncooked food that somehow manifest flavors once the molecules break apart? Oh yeah. I mean, I guess too, a chemist would think of heat as like molecules moving around faster. So, you know, when they move faster and collide,

they can break apart, but they can also kind of stick together. It's like if you threw a bunch of Legos in a clothes dryer and let it go, if you had a Lego figurine. At the end, you have a pie. But they do stick together. At the end, you have Megatron. Exactly.

Or something less ordered, but stuck together in a different way. So yeah, I mean, if you think of a steak, or you know something less ordered but stuck together in a different way um so yeah i mean like if you think of like a steak um as you as you cook it first you'll get reactions between the oxygen carrying molecules in the muscle the uh the heme and the myoglobin there's like a little iron atom and uh iron is quite reactive that will react with some of the the cell membrane lipids in the cells and create that kind of like cooked beef flavor. And then as you continue heating up the outside, you'll start to generate reactions between sugars and amino acids.

There's like trace amounts of both in the kind of, you know, juices essentially. And that will create the Maillard reaction, which is a lot of people's favorite food chemical reaction because it creates the flavor of, well, well-seared steak, but also chocolate, roasted coffee, toast, brown butter, butterscotch, things like that. So any kind of delicious, toasty, nutty, brown flavor comes from that Maillard reaction. I did a lot of cooking in my life, and I would say one out of 20 times something happens by accident. I would say one out of 20 times something happens by accident. And of those accidental times, maybe one in 10 of those is, hey. And so how much of what we count as cuisine really came about by accident?

Somebody made a mistake or somebody was missing an ingredient and had to grab something else off the shelf and invent an entire new taste experience. Yeah, no, I think a lot of it comes from that, both from messing up, from adapting to, you know, straightened circumstances where you can't cook what you know how to cook. And also, you know, I guess just the right proportion of weirdos that like to mess around with things on purpose. I'm wondering about your PhD. Was that just, you just walked into a kitchen and made stuff up? I guess I like to think of it as like guided making stuff up.

Organized chaos. Organized chaos. That's the best word. So when you make a reduction in a sauce, why did the flavors become that much more concentrated? Gary, you're evaporating out the water and water's got no flavor. Exactly. So what?

I didn't ask you. You're a hard question. I didn't ask you, did I? I wanted to know for me. You did reduce sauces. That's only in France. So you're stuck with your watery liquid gravies. Is that what's going on?

Possibly. But yeah, while you're reducing, you are evaporating water. And so the taste molecules, specifically taste molecules aren't volatile. You'd have to put them under like an insane vacuum to make them evaporate. So they get more and more concentrated.

Just so that our audience knows, the less air pressure there is on the surface of anything, but let's say liquids knows the less air pressure there is on the surface of anything, but let's say liquids, the less air pressure, the more likely the molecules of that liquid, whatever it is, will jump off the surface and go into the air. So you use the term the, in a vacuum, you could possibly evaporate some of these molecules,

but in normal air pressure, you're not. Yeah. Right. Okay. So I just want to make sure everybody was understanding. Yeah, yeah, yeah. I mean, and interestingly, this practice of creating a vacuum to evaporate things at lower temperatures, a lot of bars and restaurants use that now in the form of a rotary evaporator. So they're able to distill things at, you know, 30 degrees Celsius instead of boiling. Well, how about sous vide and

i mean that's low temperature cooking too without the vacuum it's just a closed environment that you put whatever it is that you're cooking yeah you'll use like a vacuum chamber to basically like shrink wrap a piece of meat or whatever else you're cooking so then when you put it in a temperature controlled water bath you get good contact with the entire surface. Okay, last time I sous-vide, I didn't have a vacuum chamber, but I accomplished the same thing. A plastic bag. Yeah, a plastic bag. Plastic bag, yeah.

A sturdy plastic bag. If you submerge it, all the water in the plastic bag wants to get out because it wants to float up. So you just have a little straw hole in it. And as you lower it, the bag looks like it shrinks down on the food then you seal it and i have basically a vacuum packed bag yeah no it's a handy handy trick for if you don't have a vacuum sealer yours is broken i've done before yeah it's pretty cool and it works really well it's like yeah look at it it's as though it had been vacuum sealed right yeah yeah so there's a case getting back to Chuck's point.

We're not cooking it at high temperature. And so sous viding, especially meats, has become quite the rage in recent months and years. So who said, let's not sear it and still cook it? Well, no, I know what it is. They still sear it only after they sous vide it. Yeah, that's it. Exactly. And that that's it. And that's what happens.

But I've got to tell you, when you do that, it's like you're sealing in all the flavor with the sear. And it sears very quickly. Very, very quickly. That's the other thing, too. It's already almost at the right temperature. Yeah, it's almost like you pre-cooked it, really. That's all it is. That's what it is. I mean, quite literally, yeah.

Just do the red meat at 130 degrees and say, here's your steak. Just slap that puppy back on the pan. So, I mean, if you're cooking a steak on like a grill or a griddle, not sous vide, you're kind of doing, you're using like the high heat of the pan to do two things at once. One, you know, bring the interior of the steak to your desired doneness, which might be like 130 Fahrenheit, something like that. But then also create flavor on the outside of the steak by bringing it to a much higher temperature than that and hoping that not too much heat leaks into the center. So you've got to kind of like time it so that the inside and the outside are the way

that you want it. Notice how she said 135 degrees Fahrenheit. Messifying her units of measure here. As opposed to the vaporizing 135 degrees Celsius. Yes. So, Ariel, when I grew up, no one seemed to fear the idea of artificial flavoring in foods. We just viewed that as science, making things easier and faster and more profitable. And now, of course, it'd be highly objectionable to most people. What is the industry of artificial flavors look like today?

Yeah, no, I mean, there's still a huge flavor industry. It's a multi-billion dollar a year industry. I was pissed off last time I bought truffle oil, only to find out that it was artificially flavored. No truffle in the oil, baby. No truffle. And usually, you know, something like a truffle will have dozens or hundreds of different flavor molecules in its flavor profile. And usually for something like truffle oil, like one, the one that smells most strongly

of truffle. I'm blaming you for this because you could have stopped them. You could have called me right at the minute I was buying that product. Why didn't you text me, Neil? So folding back into what we were discussing just a little bit earlier about the environmental, psychological effects on flavor and taste. Why is it that foods that are bad for us taste better than foods that are good for us? Because that doesn't seem to be us evolving well to defend ourselves.

Yeah, well, I mean, I don't think that's necessarily universally true because I've had, you know, beautiful, delicious vegetables and fruits and things that are, you know, quote unquote, natural and great for you. Tell that to a five-year-old. Ariel, Ariel, we have to discount the whole interview because we know you're lying.

I mean, I love a Dorito as much as the next girl. But yeah, I mean, you know, even in food science, deliciousness is not really like a quantifiable feature. Palatability is. So, you know, we'll often talk about highly processed foods with a lot of flavor added as being highly palatable. So, yeah, it's not so much that it is the most delicious

thing that can be achieved, but that people tend to enjoy it and eat a lot of it. So, yeah, on the one side, you've got this feature of that, you know, processed shelf-stable or, you know, long-storing foods are much more profitable than fresh ones. And so there's a lot of money put into making them as processed shelf stable or you know long storing foods are much more profitable than uh than fresh ones and so there's a lot of money put into making them as palatable and you know sensorially

interesting as possible um on the other hand you've got agronomy and plant breeding and agriculture uh you know for the whole 20th century we've basically been reading all of our fruits and vegetables to be you know higher and higher yielding, grow faster, grow more uniformly. And prettiness, you got to be pretty too. Exactly. We don't want no ugly fruit. No, no, no. And, you know, if you compare an heirloom tomato, that's sort of like bulbous and

knobbly to a perfect supermarket tomato, one is definitely easier to look at than the other. But yeah, I mean, essentially a huge amount of time and money has been spent into basically optimizing everything except flavor in plants and ingredients. Like if you look at like just corn, if you look at corn from 200 years ago, you will not recognize it. It just doesn't look. Go back to caveman days. There were these tiny little corn stalks. Teosint. Yeah. The original ancestral corn. No just doesn't look. Go back to caveman days. There were these tiny little corn stalks.

Teosint, yeah. The original ancestral corn. No, you're right. So Ariel, before we turn this over to our Q&A section with our Patreon supporters because we told them we were going to talk to you. Nice. And questions just flowed in like rivers.

Just give us a quick overview of your book, Flavorama. And who published it? HarperCollins. HarperCollins. Harvest Division of HarperCollins. It's really, you know, giving you the lay of the land and the tools that you need to understand the science of flavor

well enough to improvise with it. So I think a lot of um you know science books about food can take a kind of like bossy tone of like well this is the right thing to do or uh oh this is this is correct and um i think you know with with cooking you know what what you love what you find delicious is really uh up to you so i'd rather give people the tools to figure out how to how to achieve that easily love the the idea. Right. So this, this, this should be in everyone's kitchen is what you're saying. I think so. I think it will help.

She's definitely saying that. She is definitely saying that. Without a doubt. She's like, not only your kitchen, this would be in every kitchen of every person, you know, buy it for your friends. Right. Yeah, no, I mean, and you know, I, uh, spending time working with chefs in different restaurants who were, like, really skilled at what they do, but, like, didn't have a background in science,

I found myself explaining a lot of the same concepts over and over again and saying, like, oh, I wish I could give you a book. There's a surest force operating on book writing. Yeah, that's how it happened. Let's pivot this to our Q&A. Okay, so seeing as Noma is in a Scandinavian country, let's visit that particular region.

Frederick Johansson, hello, doctors and lords, for those who wish to be appropriately titled. Frederick from northern Sweden here. Famous dish in Sweden is surstromming. It's fermented stinky herring. When I was younger, I hated the smell and taste, but after trying it over the years, I today believe it's the most delicious food in the world. Well, that's quite a turnaround. Yeah. How can someone's perception change so drastically? Is there then an evolution in our

tastes and flavors developing over our years as we age? tastes and flavors developing over the our years as we as we age yeah um absolutely so i guess uh search timing is a pretty extreme example um for those who haven't uh tasted it before it's uh it comes in a in a can that's sort of bulging because of all the like fermentation gases have uh it looks like a bad idea listen it to this. It sounds explosive. She's over the pin it and you throw it. No, it's recommended not to open it inside because when you put the can opener through, you can emit a jet of concentrated juices.

So yeah, just getting the food is an extreme sport. There's a health warning on the can. I think so. I've been around a can. I haven't tasted it myself because it was really too much for me, which I guess I need to remedy now that I'm braver than I was then. But yeah, so surstromming, I've heard the taste compared to dirty diapers. It's really an intense experience. But, you know, there are other things that most people don't enjoy when they first try them, they come to love. I used to work with someone whose favorite t-shirt said, what's that smell? It's either bad meat or good cheese um so there are uh yeah there there are you know processes

especially in the fermented foods that uh you know microbes can do in the american south of food that resembles this this story arc is chitlins right this pig intestines half a day yeah but seasoned yeah and that's uh yeah and i will never eat it and my my mother used to make it all the time my grandmother made it and i called it slave food because that's what it is and um i was like i'm not eating it uh you know why because if a pig came into your house and took a dump in your kitchen that is what chitlins smell like. Well, that's what I hear. Yeah, no way. No way. I mean, you literally are eating something that smells like literal poop. It's ridiculous.

It's some of the best food they've ever had in their life. It mirrors this example here. Yeah. You know why? In both cases, here's why. Because at some point, your brain capitulates and accepts the abuse that is being heaped upon you. So in Frederick's case

this is just kind of like a stinky fish Stockholm Syndrome where at some point he's just like, you know, this is actually good because all those years of abuse as a child being made to eat it finally caught up with him.

Okay, you get that off your chest yeah like the confession here i mean so yes those are two excellent examples of acquired taste but then i mean even even something like a strongly flavored cheese you know like like a camembert or a limburger um if you compare that to milk uh it's horrifying uh it's like well milk should not smell like that but then um you know we're basically built as humans to uh be skeptical of new things but then um once we eat something a few times and uh don't get sick and kind of uh record that sense memory as a as a positive one uh well we can develop a taste for just about anything actually so an arrow i the day i knew i was grown up was the first day i realized i liked blue cheese there you go i said i'm grown up now

that's uh i remember at one point i was 18 and i got a sudden craving for olives despite having like hated olives every other time yeah they're bitter they're pungent. Yeah. Now when you start drinking martinis at 12, that's all I'm saying. Okay. I keep going. Who's next up? All right. Go ahead. From hello from North Vancouver, please visit. Is it possible to genetically make vegetables taste more appealing like a chocolate flavor or Oreo flavor. Yes, I am Canadian. So put the letter U, some words, because U matters. That's how we see it. Yeah, well, so I have friends that are, you know,

synthetic biologists that do exactly this. Not so much with vegetables, but it is definitely possible to, you know, most since flavor is molecules. I just have to clarify here nowadays when we refer to someone as a synthetic biologist they're freaking making life right they're genetically modifying organisms the gmo got a bad word in recent decades exactly you found another thing to call them so it's not that the biologists themselves are synthetic they're, but they're making synthetic food types. Yeah, well, I mean, one famous example, and I think this is actually in use in the flavor industry,

is that once you figure out the kind of enzymatic pathway that a plant like vanilla or rose uses to make one of its flavor or smell molecules, of its flavor or smell molecules, people have tried, you know, inserting those genes into a yeast and making a fermentation that's kind of like brewing beer, actually. But the end result is a lot of flavor molecules. From the beginning, not added later. Exactly, exactly.

So you basically brew up vanilla flavor and then purify it out of the sort of yeast soup. In theory, that's possible. I do know quite a few people, I mean, going back to our, like, sort of, mousse soup. In theory, that's possible. I do know quite a few people, I mean, going back to our, like, you know, earlier conversation about how, you know, all the flavor has been bred out of vegetables. So, you know, when people say, like, tomatoes don't taste like tomatoes when I was a kid, like, it's literally true. Most commercially available fruits and vegetables have very little flavor compared to, know 50 years ago there are people that are uh interested in changing that um i have uh i have some friends at washington state university that

have a bread lab so they they breed wheat is that st louis uh oh no uh wsu in north of seattle so it would be in washington state i'm thinking of washington university washington university yeah is in st louis um yeah so so there there are like academic wheat breeders and vegetable breeders that, you know, up until maybe 10 or 15 years ago would have been making these terrible supermarket varieties that are like high yielding, etc., that have kind of gone rogue and are really interested in making seeds for fruits and vegetables that express a lot of flavor and are easier to grow maybe than little seeds, which is what people have traditionally tried to use if they want like a really delicious tomato or wheat. I don't know if we have time to go here, but

I heard, and it made sense to me, that the reason why children don't like vegetables, but as adults, we're either neutral to them or come to like them. children don't like vegetables, but as adults we're either neutral to them or come to like them, children don't like vegetables because vegetables on average are bitter. And most poisons in nature are bitter. And poisons are much more potent on a small body, such as an infant or child or toddler, than they are on an adult. So that this was an evolutionary resistance

to not dying by eating something that was poisonous. Yeah, no, that's exactly how it works. Children also, babies and children, have more taste buds than adults. So we're born with a lot of taste buds that we sort of gradually lose over our lifetimes. So, you know, everything they're tasting is more intense than what an adult will taste. I can imagine a whole new TV show where children who can't otherwise speak yet, you just hear their thoughts. Stop shoving this down my throat.

I can taste this and you can't because you're old but i could just i could picture the whole dialogue yeah yeah um yeah well i mean our tastes are and our like enjoyment of tastes is like pretty hardwired so like babies are born liking sweet foods liking umami being very like disgusted and aversive uh towards towards bitter and breast milk is is sweet so yeah it is sweet yeah um so you know than what we think of as regular milk yeah cow milk yeah good source of calories uh and human breast milk because all mammals would have breast so this is true it's in the name uh

It's in the name. So next up, give me another question here. All right. Ali Khan Hemraj says, hello, Dr. Tyson, Lord Chuck, Dr. Johnson, Gary. My question is, how is molecular gastronomy change the way we eat in the future? Is everything just going to taste like chicken? Where'd that come from anyway? Tastes like chicken.

Yeah, I think, you know, not to harp on about the destruction of flavor in the 20th century, but, you know, if you eat an heirloom chicken or a wild chicken, it has a very intense flavor. So the kind of blandness of current chicken is a relatively new phenomenon. So maybe it will taste like chicken, but tastes like, you know, the chicken of the 19th century or the, you know, red jungle fowl. Ariel, what does chicken taste like?

I'm sorry. That's a good question. That's a deeper question than any of us ever expected it would be. Yeah. Molecular gastronomy this is thinking about food and cooking on a molecular level rather than just on a macroscopic level yeah so do you see a trend line here in the future yeah i mean you know so you've got uh like large food companies paying you know more and more attention to flavor especially as they're making you know

plant-based meats and things like this. But I think other people working on food, whether that's farmers, seed breeders, chefs, are finding a lot of different ways that understanding the molecular side of things helps them do what they need to do. So yeah, no, I think it's going to change the way we eat in so many different ways that there's not going to be like one particular trend. And if you don't like it.

But in the end, chicken will always taste like chicken. Okay. Whichever side of the road it's on. Exactly. Right. Next question. Renee A. Chen. Hello, everyone from Silver Spring, Maryland.

When we ultimately inhabit the moon, how will cooking differ? Will the boiling and freezing points of water change will food cook faster or slower will we need special equipment i can handle this ariel if we no i think i think you actually have more experience with this than uh than i do yeah yeah sure so if you have a hab module presumably it's pressurized and if it's pressurized then everything is normal the The boiling points are normal. As we discussed earlier, the pressure of air or of an atmosphere on top of the liquid affects what evaporates and what doesn't and at what temperature. So now the fact that there's lower gravity, I don't know that gravity matters much, Ariel, in food preparations.

What do you think? I don't know that gravity matters much, Ariel, in food preparations. What do you think? I don't know for cooking. I know that for people that have been trying to research growing food in microgravity, water has such high surface tension that it's sticky in a way that most plants are not used to dealing with. So in terms of growing food, definitely. In terms of cooking, probably not so much. Probably not so much. Probably not so much.

But I can tell you this, with a lower gravity, honey will never pour out of it. If you're waiting for the ketchup to come out of the ketchup bottle. So I think, yeah, that'll be quite frustrating. But if they don't pressurize the cabin, that's the old running joke. You know, the restaurants on the moon would all be fascinating, but they'd have no atmosphere. Well, I guess you wouldn't have barbecue outside, would you, on the moon? Well, you could have barbecue, provided your source of heat does not require oxygen. Yeah, yeah.

No flame. Hard to get all those smoke flavors from wood without mixing some oxygen in. Yeah, yeah. Okay. Let's see if we get one more in here. Willest74. Hello, doctors and comedic lord. Will from Hawaii here.

In the movie The Matrix, they were discussing if machines have gotten the flavors wrong, to which Dozer replies, it's a single cell protein combined with synthetic aminos, vitamins, I say vitamins, and minerals, everything the body needs. What do you think about getting the flavor wrong? If food is made up of certain chemicals and combinations thereof, will food taste the same to everyone who has the same similar receptors, or is this more philosophical versus scientific perspective like when determining how red is the red one sees if red at all yeah well one of the reasons that like the science of flavor is not more well known in the public is

um we didn't really have the instrument sensitive enough to tell what was making flavor until the last like 40 years or so and there's even yeah there's been papers in the last 10 to 15 years kind of like identifying completely new natural flavor molecules that we just had no idea about because they were in such infinitesimally tiny amounts that a gas chromatograph mass spectrometer couldn't sense it but our nose could sense it. So, I mean, like provided that you have perfect data and then could access all of those chemicals, in theory, it's definitely possible.

But it's something that, you know, practically is vitrity. What I think the matrix got wrong there, it assumed that the flavor was something separate and distinct from the molecular structure of what you were eating. But if you've reproduced the molecular structure of it all it should have the flavors that it would have in the authentic version of itself so yeah i think they got that wrong and you know like there's experience in eating where um you know we have things like glutamate receptors in our intestines so that doesn't't create the sensation of umami. But yeah, the experience of eating is kind of shaped by chemistry even after we swallow.

Yeah, like you have sugar receptors in your gut as well. Exactly. So it prepares your brain to receive the signal that, hey, I'm eating sugar. This is great. Yeah. Gary, we got time for one last question. One. All right.

Here we go. Bruce Ryan. Hi, gents. And of course, Ariel. He's from Alexandria in Virginia. I always wondered why carbon dioxide sticks to water to make fizzy drinks. Do other gases work the same way? If so, why don't people make fizzy drinks with helium? Thanks for all you do. Well, you're welcome, sir. Now, that would be fun, huh? Thanks for all you do. Well, you're welcome, sir. Yeah. That would be fun, huh?

Yeah. So carbon dioxide sticks to water because gases are able to dissolve in water and all gases, I think, are able to dissolve in water. Beer gas. So if you're setting up a tap system at your restaurant and using gas to dispense it is usually a mixture of carbon dioxide and nitrogen or nitrous oxide. Depending on what beer you're pouring you'll use like a slightly different ratio so that like really creamy head on a guinness is often because there's like a lot more nitrous oxide in in the gas um but of course you know

carbon dioxide and nitrous oxide have different flavors um nitrous oxide uh it's kind of creamy um it's uh you know it's got that sort of like whipped cream smell a little bit. I thought it was laughing gas. Isn't that nitrous oxide laughing gas? Yes. I'm misremembering that. So there are also recreational uses for whipped cream devices. Whip it more, baby. I don't know.

Yes, exactly. All right. But yeah, no, carbon dioxide is special because it has a prickly flavor. And we're not actually sure yet what that mechanism is, whether we have a distinct carbonation taste sensor or if it's interacting in a special way with our sour receptor. You're telling me dissolved helium wouldn't have a prickly sensation on your tongue? Probably not. And, you know, you consider

like, you know, a human's experience with carbon dioxide. You know, usually if you're breathing in a lot of carbon dioxide, you're in a lot of danger because you're about to suffocate. So, you know, our suffocation reflex is actually from like high carbon dioxide as opposed to like low oxygen. So it's a little bit masochistic, I guess, that we like to, you know, just micro dose on suffocation. Look at that Pepsi. It's your new auto erotic asphyxiation.

Flirting with danger. Yeah. Who would have thought? All right. We got to end it there guys. Ariel, thanks for coming back on to star talk. I mean,

we should have you more awesome. Yeah, it's a lot of fun. I'd love end it there, guys. Ariel, thanks for coming back on to StarTalk. I mean, we should have you more often. Yeah, it's a lot of fun. Yeah, I'd love to. Just let me know. There's like 10 other subjects I wanted to cover. There wasn't any time. And we went over anyway. Actually, we just learned you are a resident in the city.

So you come by my office. And we could totally make this maybe a regular thing. Amazing. On the food spectrum. I would love that. And next time, we'll do it with the taste test. Oh, yeah. Bring some of your damn food.

I will run so many tests on you guys. It'll be great fun. That's not what we said. We didn't say that. You have to take the test and then we can eat some fun things. All right, Ariel, delighted to have you back on. And watch out for her book, which hit the stands

just a few months ago. Flavorama. Flavorama. Yes. Thank you so much. Give me the full subtitle of that book. Oh, A Guide to Unlocking

the Art and Science of Flavor. I love it. When you put art and science in the same sentence, you know it's going to be good. All right, Gary, good to have you. As you know.

Good to have you there. This has been StarTalk Special Edition. As always, I bid you to keep looking up.