Guest Episode: The Umami Mama by Unexplainable

39m
Gastropod is excited to present this guest episode of Unexplainable. For thousands of years, there have been four basic tastes recognized across cultures. But thanks to Kumiko Ninomiya (a.k.a. the Umami Mama), scientists finally accepted a fifth. So could there be even more?
Learn more about your ad choices. Visit podcastchoices.com/adchoices

Listen and follow along

Transcript

Hello, Gastropod listeners.

We have something special for you today.

It's an episode from one of our fellow podcasts in the Vox Media Podcast Network, a really fun show called Unexplainable.

Unexplainable is a science show that explores everything we don't know.

Every week, host Noam Hasenfeld is joined by experts and reporters to take a look at some of the most fascinating, unanswered questions in science and the mind-bending ways scientists are trying to answer them.

There's a new episode every Wednesday.

They cover everything from what dinosaurs might have sounded like to why we dream and whether you should take a DNA ancestry test.

In this episode, Unexplainable takes on the mystery of taste.

Listen now for the story of the woman who campaigned for decades to get umami accepted as one of the five basic tastes.

She's the umami mama.

And after you listen to her story, you can follow and subscribe to Unexplainable wherever you get your podcasts.

We will be back in a couple of weeks with a fresh new gastropod episode.

And now enjoy Unexplainable.

Support for this show comes from Pure Leaf Iced Tea.

When you find yourself in the afternoon slump, you need the right thing to make you bounce back.

You need Pure Leaf Iced Tea.

It's real brewed tea made in a variety of bold flavors with just the right amount of naturally occurring caffeine.

You're left feeling refreshed and revitalized so you can be ready to take on what's next.

The next time you need to hit the reset button, grab a Pure Leaf iced tea.

Time for a tea break?

Time for a Pure Leaf.

Support for this show is brought to you by CVS CareMark.

CVS Caremark plays an important role in the healthcare ecosystem and provides unmatched value to those they serve.

They do this by effectively managing costs and providing the right access and personalized support.

The care, empathy, and knowledge that CVS CareMark provides its customers is proven time and time again with their 94% customer satisfaction rating.

Go to cmk.co slash stories to learn how we help you provide the affordability, support, and access your members need.

It's Unexplainable, I'm Noam Hasenfeld, and this is our fourth episode of Making Sense, our series on some of the most perplexing questions about our senses.

Last week, we talked about the mysteries of smell, and this week, senior producer Meredith Hodenott brings us a story about the fuzzy borders of our sense of taste.

The science behind how things taste has been an organizing principle in my life.

It's led me to chemistry labs and test kitchens and science podcasts, but I've never met anyone as devoted to the science of a single taste as Kumiko Ninumiya.

My nickname is umami mama.

Many people don't know about my exact name, but they know umami mama.

Kumiko, the umami mama, is a biochemist and researcher.

I am always talking about umami, umami, umami.

The umami that Kumiko is always talking about has always been a part of food, but it wasn't identified until 1908.

That year, a Japanese chemist, Kikunae Ikeda, distilled pure glutamate salt from big sheets of a seaweed called kombu, a foundational ingredient in Japanese cuisine.

This salt, monosodium glutamate, or MSG, was more than just salty, but it wasn't exactly sour or bitter or sweet either.

Ikeda believed that MSG had a totally distinct taste and that it was the basis of deliciousness, or umai in Japanese, and so he called it umami.

if you eat long cooked stew or slapping chicken soup or biting

a slice of pepperoni and mushroom pizza you feel a long-lasting and very comfortable aftertaste and that's umami umami is like a baseline In a dish, you might not even notice it, distracted by the harmonies of sweet and sour and salty and maybe a discordant note of bitter.

But umami is there.

It's rich, it's deep, it builds over time.

In some ways, umami is the taste of cooking itself.

It's the taste of proteins blasted apart through heat or fermentation.

And at the heart of umami is one of those protein pieces, glutamate.

And while MSG is a pure, concentrated form of glutamate, glutamate and the umami it evokes occur naturally in foods all over the world.

Cheeses, cured meats, anchovies, tomatoes, mushrooms, seaweeds, they're all high in glutamate and all full of umami.

Ikedo was the first to really give umami a name and to sell it.

He founded Ajinamoto, which became one of the biggest MSG companies in the world.

But in the 1970s, Ajinamoto encountered a problem.

We have a big problem about anti-MSG groups around the world, especially in the United States.

A letter to the editor in the New England Journal of Medicine suggested that MSG caused weakness and dizziness, chest pain, and all these other vague symptoms they called Chinese restaurant syndrome.

People say no, MSG.

MSG is bad for hairs, and the MSGs are just chemical.

This sparked a xenophobic panic across the U.S.

and demonized MSG.

It's a neurotoxin.

Chinese food is packed with MSG.

MSG.

MSG-laden Chinese food gives you headaches, migraines, allergies, dizziness.

And learning disabilities.

I had MSG poisoning.

I know.

Ajinamoto and other MSG companies poured tons of research dollars into proving that their products were safe.

Private institutions, public government research, it all came back with the same conclusion.

MSG is safe.

Yeah, you know what causes Chinese restaurant syndrome?

Racism.

But a dark cloud of bad press still hung over the MSG industry.

They wanted to change the conversation entirely.

And so Ajinamoto hired Kumiko.

My mission was to promote studies on Gulf Damien and umami around the world.

Ajinamoto tasked Kumiko with getting the scientific community to accept umami as its own basic taste.

When I started working for research and study on umami taste, I was not so interested in the umami taste.

My boss just say you are in charge of this work and it's a kind of my life work.

Did you know that it was gonna be your life work when you were first given that assignment?

No.

At that time

I was always thinking how to quit my job.

She didn't quit.

Instead, she launched a multidisciplinary, international, decades-long campaign that changed the field of sensory science forever.

That was my big challenge.

And in the process of pushing for worldwide recognition of Umami, her work raised more questions.

How many tastes are out there?

waiting for the scientific establishment to recognize?

And how do we even define a taste to begin with?

All knowledge must come through the senses.

All that we perceive and all of the awareness of our daily existence.

Light?

Jabo, rainbow, oh my god.

Sound?

Listen to me, just a dream.

Touch?

Swishes?

Odors

and tastes.

What are your thoughts concerning the human senses?

As meat and wine are nourishment to the body,

the senses provide nutriment to the soul.

All that we perceive, see, all of the awareness.

Hearing, all knowledge must come through the senses.

I have an incredible sense of touch.

All that we perceive, tasting, all of the awareness.

Smelling, all knowledge must come through the senses.

Doesn't make sense.

Senna weave awful.

Sana weave off.

So, what was Kumiko trying to achieve here?

What does it mean for something to be a taste?

For thousands of years, it was a pretty exclusive club.

Traditionally, it's been believed that there are four basic tastes that are built into us.

This is Gary Beacham.

He's the former director of the Monel Chemical Census Center, a nonprofit research institute.

Gary's interested in the big four tastes, but also the evolutionary narrative of how each taste helped our ancestors answer the question, what should I put in my mouth?

So first off, there's sweet.

Sweet, that is supposedly a signal for calories and sugars.

Next up is salty, a signal for sodium, which is an essential mineral for life.

And so animals are built to be able to detect it and to like it.

Then there's bitter.

Bitter presumably helps us spit out poisons.

But also many poisons at low levels are medicinal, and so it's been used actually as a way to identify medicines as well.

And finally, sour.

Sour is this response to unripe foods.

The exact function of that sensory system is not so clear.

So the big four, sweet, salty, bitter, and sour.

Those were the ideas that went back thousands of years.

The Chinese, the Indians, the Greeks, many, many societies all through the world named those four as the basic part of taste.

So in the 80s, when Gary started hearing about the campaign to make umami a basic taste, he was intrigued to a point.

There was certainly

a lot of skepticism in the U.S.

that this was really maybe something that was not a real taste, or it wasn't certainly a basic taste the same way sweet, sour, salty, bitter is.

And maybe it was all a marketing ploy to try to sell amino acids and particularly MSG.

My mission is not to sell MSG.

My mission is to let people understand umami.

Kumiko knew that scientists were wary of her motives, but she had a clear goal ahead of her.

The goal is to make her network with scientists who are interested in umami research or glutamate in our body and food.

Glutamate is an amino acid, a building block for proteins.

It's important in food science, nutrition, physiology, but it's also a neurotransmitter, like one of the most abundant chemicals in the brain.

So there was a lot of research interest in glutamate across a lot of fields.

And Kumiko wanted these researchers to communicate with each other.

Usually, the food scientists make a conversation with food scientists, but it was very difficult to make a good communication between food scientists and brain scientists, food scientists, and nutritionists.

That was very hard work to make a good communication among all the research areas scientists.

Kumiko thought that good communication could get these scientists excited about studying umami as a taste.

And that excitement was the key to her plan.

Like any other part of human culture, science has fads.

Sarah Tracy is a historian of science, and she has a book coming out all about the history of umami.

Everyone talked about the brain in the 90s and the Human Genome Project, and then it was all about the the gut and the odds, you know?

So I think umami is an interesting example of a very conscious and careful

investment in the creation or fostering of scientific excitement.

The idea of whether umami was a taste had the potential to be the next cool thing to study.

Like, how do you even define a new taste?

There hadn't been one for thousands of years.

We've had the basic four for millennia.

It takes a lot of PR money.

It takes a lot of research dollars.

It takes a lot of impetus to change our ideas about how to define the body.

After the break, Halcumiko started to redefine our scientific understanding of taste.

With the Spark Cash Plus card from Capital One, you can earn unlimited 2% cash back on every purchase.

And you get big purchasing power.

So your business can spend more and earn more.

Stephen, Brandon, and Bruno, the business owners of SandCloud, reinvested their 2% cash back to help build their retail presence.

Now, that's serious business.

What could the Spark Cash Plus card from Capital One do for your business?

Capital One, what's in your wallet?

Find out more at capital1.com/slash sparkcash plus.

Terms apply.

Thumbtack presents project paralysis.

I was cornered.

Sweat gathered above my furrowed brow and my mind was racing.

I wondered who would be left standing when the droplets fell, me or the clawed sink.

Drain cleaner and pipe snake clenched in my weary fist, I stepped toward the sink and then, wait, why am I stressing?

I have thumbtack.

I can easily search for a top-rated plumber in the Bay Area, read reviews, and compare prices, all on the app.

Thumbtack knows homes.

Download the app today.

Welcome back.

I'm Meredith Hodnott, and this is Unexplainable.

In order to get umami accepted as a basic taste, Kumiko, with the backing of Ajinomoto, began organizing international symposiums on umami taste.

They were very good meetings in the sense that they brought the very best people who were doing taste work in the world.

Gary met neurologists and nutritionists, molecular biologists, and medical doctors, all studying glutamate and all brought together by Kumiko to discuss whether umami was a basic taste.

What they were cleverly doing is trying to get people interested in doing research in this area.

And that was,

in retrospect, a good thing, although it could have been a dangerous thing, of course.

Dangerous because industry-sponsored science is kind of suspect.

Companies often get the results that help them tell the stories that they want to sell.

There was no question that there was funding coming from commercial organizations, which had an ulterior motive, you could say.

And I think that that led people to actually lean over the other direction to try to make sure that the research they were doing was not influenced by anything like that.

Throughout the 80s and 90s, Kumiko organized these umami taste conferences.

But she kept coming up against a problem, the translation from glutamate to umami.

In that time, the researchers themselves don't know about the taste quality of umami.

The scientists scientists know about the glutamate in the brain, glutamate in the body, and glutamate in foods, but they don't know about what exactly umami is.

Brain scientists were shocked that glutamate, that they knew as a neurotransmitter, wasn't food at all.

People kept calling it umami, not umami.

And because the quality of umami was so subtle, that building baseline under the flash and flare of other tastes, Kumiko put together tasting sessions for these scientists.

She believed that they couldn't fully debate whether umami was a taste if they didn't have the personal experience and vocabulary to talk about it.

That's why I think the tasting is the most important part to let them understand the taste quality of umami because we are talking about the taste of umami.

So, through the symposium, I try to make her opportunity to have a tasting session about umami taste and how to find umami in the tomato or cheese and they gradually understand what umami is.

There was a not just a taste

but a feel.

It was almost like it was thick and it was it was mouth watering.

It was delicious.

Gary and other scientists understood that umami was a unique sensory experience.

But did that make it a taste?

Scientists scoured everything they knew about taste, how chemicals in food interact with the tongue, how the tongue sends signals to the brain, how the brain processes those signals.

They looked at animal models to see if other species could taste amino acids like glutamate.

And in Gary's mind, if umami was a taste, it probably had some evolutionary explanation.

So he wondered, could umami be a taste signal for proteins, just like sweetness was thought to signal calories and salty sodium.

So he worked with malnourished infants to see if they were particularly drawn to the taste of glutamate.

And he found that all the infants he studied liked the taste of MSG.

Everywhere they looked, there were promising clues, but there's no clear-cut answers.

No way to definitively say that umami was a taste.

In large part, because taste is just really hard to study.

It's the sense we understand the least,

because it is so incredibly difficult to isolate.

This is Camilla Andel Andersen.

She's a neuroscientist at International Flavors and Fragrances, a corporation that makes ingredients for processed foods and beverages.

So think of vanilla, think of banana, think of

orange.

All those are what you would perceive as smell.

A lot of what we think we're tasting is actually us smelling food from inside our mouths.

Take a cookie, for instance.

You smell the vanilla and the chocolate chips and the butter wafting up from the back of your mouth into your nose as you eat it.

One good way to actually differentiate between smell and taste is to pinch your nose.

If you pinch your nose, you wouldn't be able to smell.

And so, if you put,

let's say, a bit of cinnamon in your mouth, you pinch your nose, then all you would be detecting is a little bit of bitterness.

That's the taste.

And when you then unpinch your nose, you would perceive the cinnamon.

So that's really the smell.

And even when you take the nose out of the equation entirely and just focus on sensing chemicals in the mouth, the borders of taste are still fuzzy.

Like take spiciness.

Is spiciness a taste?

It's a molecule, capsaicin, that you're sensing in the mouth.

but it's actually activating pain and heat receptors.

So it's considered more of a kind of touch.

The same goes for astringency, menthol, and qualities like slipperiness.

Those are all mouthfeel, not taste.

But by the 90s, researchers were pretty sure that umami wasn't an aroma or a touch, though it did have an interesting mouthfeel.

And repeated tests showed that glutamate kept triggering a unique response in the brain, totally distinct from the big four.

And yet, scientists like Gary wanted more.

They wanted to know how umami worked.

You really wanted a much more compelling story as to how it's different.

What's the mechanism differentiating it?

And so the conversation of whether umami was a basic taste pivoted to molecular biology.

This was around the late 90s, and molecular biology was all the rage.

The Human Genome Project was a multi-billion dollar international collaboration to map out all the billions of DNA base pairs in the human genome.

The thought was that this would unlock the blueprint for the human body and usher in a whole new age of genetic understanding.

And in 2000, scientists started using an early draft of the Human Genome Project to zero in on taste receptors.

A taste receptor is really where the rubber meets the road in terms of taste.

Like, Looking at your tongue in the bathroom mirror, you'll see all sorts of bumps and grooves, and those are little organs called papilli.

Zooming in, the papilli are packed with taste taste buds, and each taste bud has like 50 to 100 taste cells.

Zooming in even further on the tip of each of those cells is a taste receptor, a carefully folded little protein that interacts with food on a molecular level.

And so researchers all around the world were racing to find the genes that coded these receptors for all the tastes.

All at once, these receptors were identified.

First, a bitter receptor was identified, and then a sweet receptor.

2000, 2001, 2002, that was the golden age of discovery and it was very, very exciting time.

During this taste receptor gold rush, Kamiko had one question.

What is the taste receptor of umagi?

So we tried to promote research in the United States to talk more about the taste receptor of glutamate.

And remarkably, there was a separate one for glutamate.

Right there, built into our tongues, was concrete evidence that umami was a taste.

The fact that there was a receptor for this really convinced a lot of people that if nature has given us this sensory apparatus to detect it, it must be real and it must be important.

For Kumiko, this was the culmination of years and years of work, organizing conferences, doing taste demonstrations, promoting research.

Scientists were looking for glutamate receptors because Kumiko convinced them that there was something to look for.

That was a big turning point.

Were you excited when you heard the news that they had discovered it?

Yes, yes, of course, yes.

That was a very epoch-making research result.

Everyone believed that umami is one of the basic tastes.

Umami was accepted around the world as basic taste number five.

But in pushing the scientific understanding of taste beyond the big four, umami opened up a whole new world.

How many tastes could be out there?

Are there just five basic tastes now?

Or could there be way more?

Now the race is on to see if there's a sixth taste or a seventh or a thousandth taste coming up after the break.

Support for this show comes from Pure Leaf Iced Tea.

You know that point in the afternoon when you just hit a wall?

You don't have time for self-care rituals or getting some fresh air, so maybe you grab a beverage to bring you back.

But somehow it doesn't do the trick, or it leaves you feeling even worse.

What you need is a quality break, a tea break.

And you can do that with Pure Leaf Iced Tea, real brewed tea made in a variety of bold and refreshing flavors with just the right amount of naturally occurring caffeine.

With a Pure Leaf iced tea in hand, you'll be left feeling refreshed and revitalized with a new motivation to take on what's next.

The next time you need to hit the reset button, grab a Pure Leaf Iced Tea.

Time for a tea break?

Time for a Pure Leaf.

You're basking on a beach in the Bahamas.

Now you're journeying through the jade forests of Japan.

Now you're there for your alma mater's epic win.

And now you're awake.

Womp, womp.

Which means it was all a dream.

But with millions of incredible deals on Priceline, those travel dreams can be a reality.

Download the Priceline app today, and you can save up to 60% off hotels and up to 50% off lights.

So don't just dream about that trip.

Book it with Priceline.

Creamy, salty, sweet, and oaky nuttiness.

You detect that?

Oh, I'm detecting nuttiness.

It's unexplainable.

We're back.

I'm Meredith Hodnott.

And after Kumiko's decades-long campaign, umami was accepted as a basic taste when researchers found a receptor for glutamate.

This blew up the millennia-old conception of the big four, sweet, salty, bitter, and sour.

And receptors became a new benchmark for the definition of a basic taste.

But the taste receptor discoveries didn't stop with glutamate.

Over the last 20 years, scientists have found evidence for taste receptors that detect fat, starch, calcium, even metals like iron.

And scientists started to claim that some of these might also be fundamental basic tastes.

There could be a sixth basic taste and a seventh and an eighth.

But by focusing on receptors, are they jumping the gun?

I mean, sure, finding a glutamate receptor was the critical piece of evidence that tipped the scientific community towards accepting umami as a basic taste, but that came after decades of sensory, perceptual, and neurological data.

Not to mention over a century of Japanese food traditions.

This new crop of taste candidates are starting from the receptor and working backwards.

They still need to build up all that sensory and neurological research.

So let's focus on one of the most popular candidates, fat.

Your attention, please.

There is a new taste.

Researchers now say that fat should be considered the sixth taste.

Well, duh, it's not the first.

In 2015, researchers started pushing for fat to be the sixth taste because they had found a taste receptor for fatty acids, the molecular fragments of fat.

But they still need to prove that those receptors send a conscious signal to the brain, just like scientists had done for umami.

The thing that's still very much under investigation is whether that signal from the taste receptor is sent to the brain, like whether we actually use the information.

This is Camila Andel Anderson again.

So that's where the kind of science I do comes into play, where we actually look at the brain and look at, do we see a neuroactivation to this taste?

All taste is hard to isolate from the other senses, but fat is particularly tricky.

Fat is an incredible solvent, so it's this great vehicle for aromatic compounds, the smell part of flavor.

I mean, just think about garlic-infused olive oil.

Fat also plays a fundamental role in the texture, the touch of foods.

Chocolate is so luxurious because cocoa butter melts just around body temperature, so it literally melts in your mouth.

It melts in the mouth.

Crispy, crunchy, tender, crumbly, smooth, creamy, luscious, fat is responsible for all of these touch parts of flavor.

We know that we smell fat, and we know that we sense the texture of fat, but the next question is whether we also taste fat.

To test taste and taste receptors in isolation, Camilla rigged up some pretty wild experiments.

Participants had to sit with their heads completely still.

Strapping them onto a headrest.

They wore these EEG caps with sensors all over them to measure their brain activity, and they were told to hold their breath.

So they couldn't smell.

And then they stuck out their tongues.

And we would pump three types of milk on the tongues of people.

So that would be either skim milk, whole milk, or cream.

But they couldn't swallow or close their mouths.

The taste solution would just sort of drip off into a bowl standing underneath.

So you'd need a bib in this setup as well.

I did actually use one, yeah.

And after all of this, Camilla did find some interesting brain signals.

What we saw was that we were able to discriminate

the response, the brain response, to the skim milk and the cream.

There was something we were registering that was different between these two.

So some promising evidence of a signal of fat taste being processed in the brain.

But what exactly is going on, we're not sure.

Paul Breslin is a scientist at Rutgers University.

He also works at the Monell Center.

And he studies taste pathways, the path a receptor signal takes from the tongue to the brain.

In 20 years from now, we'll probably have come to some kind of a consensus on it, but we're not there yet.

All of the potential six tastes are in this position.

Calcium, starch, metallic.

Labs around the world are trying to build the narrative, build the case of whether these should be considered tastes.

It's intriguing to say, like, we can taste fat, or we can taste potassium, or we can taste calisthenom, or maybe we can taste water.

Those are all interesting stories.

But collectively, what is taste is really the more interesting question.

What is taste?

Well, our depth of understanding has certainly grown over the past 40 years.

And because there was a concentrated research effort to dig down into the molecular machinery of taste, we've learned a lot about how our whole body interacts with the chemical world around us.

Because once scientists started finding taste receptors in the mouth, they started finding them all over the body.

In the lungs, in the pancreas, on the skin, in the intestine, in the nose, in the brain.

All of these places are using the exact same machinery, the same receptors.

These receptors aren't hooked into our conscious perception of taste.

Well, thankfully, you can't taste the inside of your small intestine with the taste receptors there.

Think of it like your pancreas is constantly tasting your blood to see how much insulin to produce.

These taste receptors are tools.

So if you think of all the different ways you can use a hammer, you can use use it to hammer something into place, you can use it to remove something, you can use it to pull nails, you can use it to put nails in.

It's the same receptor in every single one of those places, but in each place it serves a different purpose.

One scientist told me that if we had found these receptors on the pancreas, we would have called them pancreatic receptors and would have been shocked to find them on our tongues.

The fundamental issue, the fundamental question really becomes, what is the totality of the space?

What is everything that we can experience in that chemosensory world and how do these things fit together?

What is their relationship to each other?

It's a bit like the debate around whether or not Pluto is a planet.

Pluto was killed because if Pluto is a planet, then all these other moons and dwarf planets like Ceres, they could be planets too.

And some scientists have argued that we should have like over 150 planets.

In our solar system of taste, the big four, salty, sweet, sweet, bitter, and sour, they might be like gas giants, the big guys, right?

Whereas Umami is much more subtle, so maybe it's more like a little small rocky planet like Earth or Venus.

But moving out, where do we draw the line?

And ultimately, does it really matter?

Pluto is still out there, still spinning around the sun, no matter how we choose to categorize it.

And for taste, wherever we draw the line, there's still so much to explore.

What is that spatial galaxy or universe of taste?

So, our scientific definition of taste is growing and evolving, but tastes are also culturally defined.

The general public might not care about the intricacies of the molecular biology, the glutamate, the receptors, but now they care about umami.

You know, it's exciting.

I understand.

I get it.

Umami is cool.

This is Sarah Tracy again, the science historian.

To me, I don't think that we would have Umami without that industry influence.

But I mean, this is also the way so much of our understanding of taste and smell work comes to us by virtue of corporate research.

Taste is big business.

It's an industry.

And a lot of what we know about sensory science has its roots in the modern industrial food system.

Our current understanding of umami as a taste was part of a larger campaign to change the conversation about MSG, and it worked.

Without a name for the thing, how can you think with it or live with it?

Our names and our language do, in a way, forge our reality.

And so whether we call it umami or not has real effects in the world.

It's certainly a fantastic branding proposition.

And that brand was painstakingly built over decades, first within the scientific community and then beyond.

An enormous amount of science communication and promotion went into popularizing umami among chefs and food writers and tastemakers.

So the company or Aginomato Company's policy is science first, then communication, based on science.

After umami was widely accepted as a basic taste, Kumiko shifted the umami campaign to the culinary world.

And I think that umami is a taste.

So the taste is very important for chefs to create the

good

meals and excellent dishes.

That's why

I decided to make a conversation with chefs.

Top chef.

When Kumiko says top chefs, she means the most famous, the most influential chefs in the world at the time.

Because top chefs have a big voice, and

maybe the young chefs try to follow the top chefs.

So

that was a very, very challenging for me.

That was very hard work.

The popularity of Japanese cuisine exploded at the same time that food science and molecular gastronomy took hold of the culinary imagination.

And suddenly, umami was everywhere.

Umami is one of the very fashionable worlds in the United States, and people are very interested in umami, so it's a very good opportunity for us to promote more about umami.

Where we draw the line on how to define a taste may be kind of arbitrary, but it has real-life effects.

Ultimately, we live in a different scientific and culinary world because of the umami taste campaign and the umami mama my nickname was given by nobu matsuhisa is a very famous japanese chef around the world and when i first met him he told me don't come to me you will start talking about msg and i never use msg because i had a many restaurants in the united states and there are so many people hate msg don't waste your time

I every month visit him to talk about umami.

And then he gradually understood what I want to do.

And after that, he started talking about umami by himself.

And he introduced me to the guest in the restaurant.

She is world-famous umami mama.

I was so surprised.

What did he say?

This is the fourth episode of our Making Sense series.

Next week, cite in the limitations of the mind's eye.

And you know, I'd always read about things like picturing your loved one's face and this and that.

And I was like, like, why can't I picture anyone's face?

This episode was reported and produced by Meredith Hodenaut.

It was edited by Catherine Wells, Noam Hassenfeld, Brian Resnick with help from Mandy Nguyen and Bird Pinkerton.

A real team effort.

Music by Noam, Christian Ayola handled the mixing and sound design.

Research and fact-checking by me, Richard Seema, and Tori Dominguez is our audio fellow.

Special thanks to Nancy Rawson, Johnny Drain, Eliza Barclay, Nicola Twilley, and Emily Hanselman.

If you want to learn more about the history of umami, keep an eye out for Sarah Tracy's upcoming book, Delicious, The History of Monosodium Glutamate, Umami, and the Dysphoric Sublime.

And the awesome Umami song is called Umami by Noishne.

To read more about some of the topics we cover on our show or to find episode transcripts, check out our site at vox.com slash unexplainable.

And if you have thoughts about the show, you can always email us at unexplainable at vox.com.

Or you can leave us a review or a rating, which we would love as well.

Unexplainable is part of the Vox Media Podcast Network, and we will see you next week for episode five of Making Sense.

This month on Explain It To Me, we're talking about all things wellness.

We spend nearly $2 trillion on things that are supposed to make us well.

Collagen smoothies and cold plunges, Pilates classes, and fitness trackers.

But what does it actually mean to be well?

Why do we want that so badly?

And is all this money really making us healthier and happier?

That's this month on Explain It To Me, presented by Pureleaf.

Thank you to CVS CareMark for supporting this show.

CVS CareMark allows you to get the prescriptions you need, where you need, at the best price for you.

CVS CareMark allows for greater access to medication through broad, flexible network strategies.

They work with more than 64,000 pharmacies nationwide, 44% of which are independent pharmacies.

This coverage means CVS CareMark can give their members the unmatched ability to choose where and how they want to receive their prescriptions.

Go to cmk.co/slash stories to learn how we help you provide the affordability, support, and access your members need.