Are We Eating Sushi All Wrong?

I guess everybody else thought that was pretty discussed. Yeah, no one believed to him, like they thought it was gross and you know, it's raw fish. So being first grader, as everyone was yelling like yuck and gross and just shaking their heads in disbelief. And then like this, one girl raised her hand and asked him, but what sushi actually tastes like? He just smiled and said bubba. So for years I actually thought like, maybe sushi does tasting bubble gum. But of course now I do know what

it tastes like, and sushi's everywhere. But it made us wonder how did we start eating these delicious fish rolls in the first place, and how did it come to America, and are you really supposed to be eating sushi with her hands instead of your chopsticks. Let's dive in. Hey their podcast listeners, Welcome to Part Time Genius. I'm Will Pearson and as always I'm joined by my good friend man guest Ticketer and on the other side of the soundproof glass, just chowing down on a spicy tune or all.

Look at the thing, it's just drenched in soy sauce. That's our friend and producer Tristan McNeil. Tristan, why are you using the sport? Oh man, he's got the wassabi mix in there too. All these problems, but that actually brings us to what today's episode is all about, and that's an intervention for Tristan. Yeah, actually, I'm kidding, all right.

So there's a lot of common misconceptions about sushi out there, and not just about how to eat it, but how it's made, where it comes from, and even what's in it. So on today's show, we're gonna take a good hard look at what we think we know about sushi and see if we can set the records right on one

of America's most popular and misunderstood finger foods. Yeah, well, why don't we start right there, because that's amazing to be Sushi is actually a finger food, and that's actually the preferred way to eat it because sushi chefs like to loosely pack their sushi. That way you can fall a part in your mouth and the flavors can mingle better.

The problem is so many Americans are hung up on eating sushi with chopsticks that chefs in the US actually packed their sushi tightly, and that's how it will hold together when grab with the sticks. It seems like such a small thing, but a lot of people actually shy away from sushi because they think you have to use chopsticks to eat it. Really still, so Americans still don't like chopsticks. I kind of felt like we've gotten over

that by this point. Yeah, apparently not so. I was looking at this market research from you gov and they conducted the survey on chopstick proficiency. This was back in two thousand fourteen, and I found that seventies seven percent of Americans preferred to use a knife and fork over chop sticks when they eat Asian food. And most of that reason is that Americans are just not good with chopsticks.

The survey claimed that thirty four percent of the country rates is proficiency with chopsticks as fair or better, while related as a not very good or terrible. Wow. And so what about the other quarter of the country. They haven't even tried chop sticks, explains it. The good news for them is that counter to most people is thinking it's perfectly proper to eat most kinds of sushi with

your fingers, and the only exception is sashimi. You know, sushi means those thinly sliced pieces of fresh, rassy food and those are served without rice. And because rassy food can be a little slippery to handle with your hands, using chop sticks is the way to go for those. But maki rules or nagiri, you can use either chopsticks or your fingers for those. All right, So we're breaking

down the barriers on today's show. And actually, I feel like another big deterrent for people who don't eat sushi or are some of the words that you just mentioned, you know, the proper terms for different kinds of sushi, And obviously these are Japanese words that anybody can look up. But you know, for people that just want to eat lunch and not have to learn a new language while doing it, that that unknown vocabulary can actually be a

little bit in intimidating. Yeah, but if you know the definitions, it isn't intimitting at all. So like the words sushii literally means body cuts, so the whole dishes right there in its name, right, And some of the other terms are less literal, but they still give these details that can help you distinguish between the different kinds of sushi. So taking a geary for example, it's the kind of sushi that consists of a small amount of rice with

a slice of raw fish on top. And the word geary actually translates to grip or grasp, so again, in a way, that's the whole dish, right, the slice of fish grips the rice mount. And it's the same with another kind of sushi, the maki roll. And this is

what most Americans picture when they think of sushi. You know, it's the colorful circles of fish and veggies, and that's surrounded by sushi rice and then this outer layer of seaweed and the small pieces are cut from this longer cylindrical rolls that are formed using I'm sure you've seen it for those like woven bamboo mats. There's a called maki su and you can probably guess the mat is where the maki gets its name. All right, So there

you go, the most common types of sushi explained. You've got body cuts, gripping fish, and matt rolls and actually saying it out loud I can. Yeah, Yeah, it's probably best that we stick with the Japanese words. Yeah, but you know, you know what, I just realized we're only a few minutes into this discussion and we've already messed

us off. What do you mean by that? Well, we've been talking about sashimi as if it's a kind of sushi, But like I mentioned earlier, sushini doesn't actually include rice, so by definition it can't be sushi. Oh wow, you're right. But at least the mistake gives us a chance to talk about what's maybe the biggest misconception about sushi, and

that's that the word itself means raw fish. I mean, it's it's it's an easy mistake to make because we think of raw fishes like the defining component of the cuisine. But an actuality, sushi is all about the rice, and that's what the word really refers to it's that sour tasting rice. Yeah, and if you look at the history, you can actually see why rice deserves the top billing. This is another thing most people don't know, but the earliest form of sushi actually comes from China and not Japan.

It was later named narazushi, and it started as a form of food preservation back in the third or fourth century BC. It's different from the fresh fish we know today. Narzushi was actually made by packing a wooden barrel with all these layers of raw and salted fish and and then cooked rice and then they'd set this heavy weight on top and you'd let the whole thing for meant for up to a year, right, And this work just like with any other fermentation. You've got friendly bacteria that

fed on a substance. In this case it was starch and the rice, and then it produced lactic acid in turn, and the resulting acid is what helped preserve the fish by slowing the growth of harmful bacteria you know that would otherwise cause it to rot. And the technique is thought to have first been used by farmers who lived

along the Makong River in Southeast Asia. So during the rainy months, the river would sometimes flood and the water would wash tons of carp into these nearby rice paddies, and they didn't want this carp to go to waste, and so the farmers came up with a new way to store the fish until they were needed. I mean,

it's pretty ingenious. But what's funny to me about this proto sushi or early sushi, is that nobody actually ate the rice, and despite the crucial role it played in the fermentation process, the rice was just tossed away afterwards, and it was only the fish that was eaten. I mean, we are talking about super sour year old rice. I can't exactly blame them for not eating it. Yeah, but

the fish wasn't in his prime either. So I actually asked gave what it tasted like, and he was saying, after a year in the barrel, it would morph into this pungent, gelatinous, almost cheese like. I mean, it couldn't have been any better tasting than all that sur rice. That is disgusting, but you know, if it makes you

feel any better. The Japanese did start eating both the fermaute fish and the rice sometime after sushi made its way to Japan, and this was I think around the ninth century, so Buddhism was spreading throughout the country at the time, and fermitte sushi helped meat that growing desire for protein source. You know that that would fit into their meatless diet, even if it did taste pretty sour. I guess yeah. So I've read that the sour taste was actually a plus for the Japanese at that time

because the rice vinegar industry had just taken off. This was in the thirteenth century, and people actually came to appreciate a little sour flavor in their cuisine because vinegar was so popular in the markets. In fact, when Cooke's found a faster way to for men cure all that fish without the use of rice, Japanese started adding vinegar to their sushi rice just so wouldn't lose that sour taste,

all right. So, so by this point we've got non fer minute rice seasoned with vinegar, just like the kind used in sushi today. So what about the fish that when does it go from being pickled to being raw like we're used to it now. So raw fish sushi didn't actually become the norm until after refrigeration became such a big thing in the twentieth century, but it did start to crop up in some places during the eighteen hundreds.

So at that time, Tokyo or Edo as it was called back then, was fostering the next generation of sushi. And all these mobile food stalls that have begun to crowd up in the streets, and this one man, his name was Hanaya Yohi, he set himself apart from the crowd by offering what's often considered the first example of

modern nagari sushi. So Yo has a great story. He opened his stall near bridge in Tokyo that crossed the Sumida River, and not only was that area highly traffic, but it was easy access to all this fresh fish. And in fact, the fish Yohai served was so fresh that there was no need for men or cook it. All you have to do was cut into slices and hand pressed them onto mounds of vinegared rice, and the process took minutes rather than the hours of days that

his competitors were, you know, spending curing fish. The Japanese public fell immediately in love with it, and they loved the fresh taste, but they also loved the fast prep time, and his business just exploded, and all these years later, it's still the most popular kind in Japan. I think what's most surprising to me about the story is hearing

that sushi was a common street food in those early days. Like, we have this idea in the US of sushi being this really fancy, upscale cuisine, all these traditions and rules that have to be observed. It's a kind of stigma that can make sushi feel inaccessible to some people. So it's it's actually pretty cool to hear about its humble origins. Yeah, the story is helpful in making it more approachable, but let's be honest, the big reason that people view sushi

is such a posh food is the price. I mean, you can definitely find roles with imitation crab another kind of filler everywhere from grocery stores to gas stations, airports, but anything with actual sushi grade sushi is gonna cost you. But it's definitely true, and I know that's the case even in Japan, where rising costs have made sushi much more of a special occasion food than that maybe it

once was. Yeah, I don't think the average Japanese citizens would dispute that quality sushi is pricy and worth the price, But the bigger sticking point for them would actually be what Americans due to a food that costs so much. Because I'm not sure if you've noticed, but we don't tend to respect sushi the way it ought to be.

I saw you given that side, I go answer Tristan that I don't want to pick on him anymore, but I will mention as a general public service announcement that you're you're really only supposed to use a tiny bit of soy sauce with your sushi, you know, so you

don't drown out the other flavors. Most Japanese sushi chefs actually brush a little bit of their own homemade sauce right onto each piece of fish before served, And the same thing happens with with sabi, you know, when when needed, chefs will include some fresh was sabi between the fish and the rice. Of course, none of this really happens in the US, because chefs know that American sushi eaters like to add those condiments themselves, you know, often to

access that. I've told you the story about my father in law when we were at a restaurant one time years ago, and he just had this brain lapse and for some reason was thinking that it was avocado. Took a big bite of was sabi, just said, oh, dear Lord, and then turn bright red. But yeah, my daughter did the same thing. She's like guacamole. Yes, and that is

on fire. But I mean it makes sense, right, I. I kind of wish we did it the Japanese way, And it seems like a better system than diting this like big stack of sushi and dipping it in soy sauce and hang it all fall apart. That's just so messy, definitely, you know. I I did pick up a few tips on the subject though, from Gero on No you know, the world famous sushi chef was in the documentary that

Netflix seemed to suggest to everyone in the world. He says that the best way to apply soy sauce after the fact is by dipping a piece of pickle ginger and then dabbing it across the top of the fish. I feel like that's a sushi life, yeah, isn't it. I mean, you know. He also has some solid advice for people who want to eat a geary using chopsticks. He suggests they think of the sushi as a portable shrine.

Place your chopsticks parallel to the tray as if they're the shrines carrying poles, and lift up the sushi by grasping it along its sides. If you grasp it through its middle with your chopsticks, it will surely fall apart. I love that he references shrines carrying poles, like everyone knows that shrine should be carried with poles, right, exactly. Um, But still that that's a great tip for Americans. So

what are you saying? We talked a little bit about how America developed a taste for raw fish in the first place. Yeah, And to help with that, let's call up Trevor Courson. So he wrote an amazing book called The Story of Sushi, and I'm pretty sure he can tell us how it made the trip state side. Our guest today is the author of a fascinating book called the Story of Sushi, an unlikely saga of raw fish and rice. Trevor Courson. Welcome to Part Time Genius. Thanks

for having me on. Trevor, this isn't the first book you've written that was related to see Life. Your first book, which got a ton of critical acclaim was the Secret Life of Lobsters. So I'm curious what turned your interests towards sushi and writing this book. I had gone to Japan just kind of by accident when I was a high school student on this summer scholarship that I just happened to get, and it was I went and lived with a homestake family, and so I had I always

had that experience. It was always issued in Japan. I ended up going back later as a college student and studying Japanese language and living in Japan for a while. Um so uh. And the thing that had happened before I went to Japan the first time this was and so sushi was still very unusual at that time, and my high school teacher said, oh, you're going to Japan this summer the scholarship. The thing is you're gonna have to not be able to eat raw fish. You don't

have to know how to eat sushi. And so there was like one sushi restaurant in town, and my teacher bought a box to takeout sushi, brought up to school and made me eat it, like, sit down in the office, try eating to prepare me for this, And I thought, wow, here's the cuisine that is truly repulsive, and like, I was horrible, How am I going to survive this experience?

But the funny thing that happened was when I got to Japan and I was living in this home state family and they took me out to their local sushi bar, and I realized what the whole experience was at that point that it was like this amazing, really fun social experience where you didn't order, you sat at the bar with a bunch of other people from the neighborhood, and the sushi chef was like this friendly neighborhood bartender and you just like started giving you these amazing things that

you didn't know what they were, and you sort of explain a little bit about each one, and this kind of series of small surprises that occurred, as you said, at the sushi bar and interacted with the chef and everything, and what what troubled me was like when I would try to eat sushi back in the States after that, it was never the same, Like I was never having

that experience that had made sushi so wonderful. So I like decided to make it my mission after this lobster book, you know, did so well, my publisher was like, well, can you do anything else on sea food because this was clearly resonating, and uh, it's like what about what about sushi? And that's how the Sushi book get started.

And I tried to like try to educate American readers. Um, you know what the Japanese sushi experience is actually, like it's very very different, and the whole history of sushi and the experience is very different from from what we tend to think of in the US. Yeah, and we touch a little on that in this episode. But I've heard you talk about the fact that we what we consider as valuable in sushi has changed over the years. Can you talk a little bit about that. Yeah, this

is so fascinating. And I didn't really realize this either until I started digging into the historical research. Um but if you ask any you know, like traditional Japanese sushi chef today, they'll tell you that like blue fin tuna is the pinnacle of of authentic Japanese sushi, especially the the belly cut to the toro, right, that's sort of

melt in your mouth and station. The weird thing is, when I started looking into the history of this, the if you went back a hundred years um in early nineteen hundred, for example, sushi was very very different the traditional Japanese sushi that they were eating at that time. Tuna was considered a garbage fish. You would never eat tuna,

possibly avoid it. It was it was considered like very low class and um, if you had to eat tuna, they would like they would marinated in soy sauce or buried in the ground, like do all these things to like try to get rid of the flavor of And at the time, what what actually was considered desirable sushi ingredients were um, smaller fish that had lighter flesh like the silvery or lighter flesh, fish that had more of a like kind of a crunchy text you're almost to eat.

A lot of shellfish were considered very desirable. Flounder and sea bream were considered like the pinnacle of fine sushi, especially the kind of juwier parts of the flashood. It's completely different that the culinary values have completely changed over the past century, and has this changed the way you think about sushi when you're in a restaurant and ordering it for yourself. Yeah, I mean the thing is when you sit down at the sushi bar, a lot of chefs or you know, if we often we just order

what we're used to. We order the usual um suspects, the tuna belly, the famine, the yellowtail, uh sweet feel. And what I learned in my research is that none of those is a traditional Japanese sushi ingredient. Uh. Those are all recent inventions. And trying to understand this, I realized that the blue thing tunam is it was an invention of the Japanese UM Airlines in the nineteen seventies.

They were uh flying their planes full of Sony walkman's over to the US and flying them back empty, and they were trying to find something they could put in the planes on the way back, and they got the idea, well, maybe you know, there's some kind of like sea food in North America that people will eat, and and it turned out there wasn't Like they even looked into tuna, and no one would eat. No one ate tuna like

maybe you'd open a can occasionally. But they were trying to get a tuna as possibly an ingredient they could fly back and sell in Japan, and no one was eating it. And everybody thought the idea was ludicrous. So it was in my my colleague Sasha Istenberg and journalists to kind of exposed this story. It was a cargo executive at Japan Airlines who who who like designed and built the cryogenic freezer containers and who developed the market that kind of turned blue con tuna into a global

sushi ingredient that they started marketing and selling. And that's why we have it today, and that's why everybody believes that the traditional chapane sushi ingredim but it's not at all. And so once I realized this, I started asking this, well, what what would you have? You know, what's the more old fashioned other sushi ingredients besides tuna, And there's all these other things that they know how to prepare and

serve that are so interesting to eat. So to answer your question, I just don't eat blue intuna anymore at all. In fact, I find my sushi eating experience has become much more interesting as a result, because there's all these other local um seasonal ingredients and smaller fish and shellfish and weird things that are just much more fun and interesting. And there's some ships who are starting to get back to that now and it's really cool to see happening.

That's really that, that's really fascinating. You know, speaking of traditional sushi, could you tell us the story behind the California role and whether or not you can get them in Japan. Yeah, the California role we kind of assuming that it was. It was obviously because of the name it invented specifically to um, you know, Americans, interesting meeting sushi. That's sort of true. But the evolution of the California

was what kind of happened over time. It wasn't immediate, and actually it started out as uh menu item for actually Japanese businessmen and stuff in Los Angeles, So it did originate in California, but it wasn't for American customers. The problem was at that time, just building off the tuna story, it was very hard to get batty tuna in Los Angeles in the um you know, or the seventies and eighties, when when sushi started to become more

popular there. Uh and so one of the sushi restaurants in Little Tokyo and Los Angeles, because they didn't yet have the ability to kind of fly these tuna fish all over the world, they thought, well, how can we kind of recreate that batty um tuna belly sensation, and a realized that they California may not made a lot of petty tuna, but they had a ton of avocados, And so they started experimenting mixing avocado in with different kinds of fish to see if they could create the

same sensation we would get when they ate petty tuna. But and tried uh, I think shrimp and a couple other things first, and finals finally somebody settled on crab meat and avocado as being the best sort of fox substitute for fortuna belly. So that was the original introduction of avocado into sushi um. But the real innovation that turned that created the California we roll we know today wasn't until someone invented what we what is called noticed

the inside out roll. And this is the typical sushi role that we see in America all over the place today. Um, we don't even realize because it's so ubiquitous. But if the rice is on the outside of the role like a California role, that's actually not even at all part of Japan. The sushi tradition that was a really key American invention because apparently Americans at first found the idea

of eating seaweed paper. Somehow it turn off and seaweed roles they were always made with the seaweed paper around the outside. And actually the whole point of it was that the seaweed paper, the nori was was wonderful to eat that way because it was crunchy. So you have this crunchy outside and the soft rights on the inside. But that was the whole point. But Americans wouldn't eat that because we were freaked out by seaweed paper, so they flipped it inside out with the seaweed on the

inside where we couldn't see. It totally defeats the purpose because now the seaweeds all soggy and wet and not crunchy anymore. But it's got American team. So it was a combination of bringing avocado into the mix and then flipping the role inside out that ultimately resulted in the California role. Oh that's really interesting, and I'm curious has any of that American influence made its way back to

Japan and the way they make sushi now, right? Yeah, Yeah, The other part of your question is that yes it has, and um, when when I was researching this in Los Angeles. Um, you'd have Japanese tourists coming over and getting all excited to order, you know, um, all the different weird American roles and Thanksgiving role and she steak role like so

now it's it's been. It's been actually so intriguing to Japanese customers to have this American style sushi that it has now been re imported to Japan and you'll find all kinds of um, weird American style uh sushi roles being sold in Japan now too. And um, they tend to call it perhaps suplimistically creative sushi. It's like it's I can say, sushi is the creative sushi uh. And also weird kinds of sushi that we don't even have in the US, um, you know, like corn and hamburger sushi.

And just like it's completely open season with all kinds of weird things. Now, well, this has been fascinating and I hope all of our listeners will check out your book, The Story of Sushi un Likely, Saga of raw Fish and Rice Trevor Course, And thanks so much for joining us on part time genius. Great to be with you. Thanks for having me. You're listening to part time genius, and we're talking about the surprising history and little known

secrets that make up the sushi experience. Okay, Mango, So we've already covered sushi's ancient origins and how it was first brought to America during the nineteen fifties and sixties, So now we should talk about some of the differences between the sushi cultures of Japan and the US. Sure, so we mentioned before the break that many Americans view sushi eating as the solemn experience, like they're in some kind of food temple and are about to take part

in a religious right or something. But what if I'm during my research is that most of it is in our heads and that people in Japan actually have this much more relaxed approach to the sushi. For example, we we have a lot of upscales sit down sushi restaurants in the US, and we ru's menus with I don't know twenty or thirty different roles and make our selections and then we just wait for the food to be

brought to our tables. But in Japan, most sushi has just served at a bar and the menu choices changed based on what the chef has on hand. Well, so, so sushi choices are actually more limited in Japan. I wouldn't have guessed that. Yeah, So Japanese sushi bars don't share that American expectation of variety. Instead, they concentrate on keeping the quality super high for the few items they

do have. And part of the reason for that difference is that the seafood in Japan is largely caught locally, so for certain kind of fishes and in season, then you won't find it on the menu. And compare that to the U s where I think it's eighty five percent of the seafood we has been imported, which means more species are available year round, but also that all

the fish has been frozen at some point. Yeah, and I think that quality is probably worth the trade off over the variety, agreed, which is why Japan doesn't have so many of those like catch all restaurants we find in the US. So a sushi bar in Japan only serves sushi, and if you want ramen or yaka tori, then you'll have to go someplace else. Yeah, and I can appreciate that that idea of that, Like we do one thing here and we do it right. But but

let's talk a little bit about the atmosphere. Well, what's that like in a in a place like that in a sushi bar in Japan. Yeah, so again we have this idea of the stoic, silent sushi chef who's, you know, keenly focused on his work and won't interact with anyone and can't be disturbed. But sushi chefs can be reserved and they can be zen like at times. But the ones in Japan often are more like, uh, like your

neighborhood bartender. So they're chatting with customers and making recommendations, and they're interacting in this way that's actually part of a sushi chef's training. So well, while there's a high level of respect for the craft, most sushi chefs are still totally approachable and friendly, which is nice to hear that. It makes me wonder where we got some of these ideas. I mean, did we just make up all this stuff about sushi chefs being like deadly serious or how did

this come to be? Yeah? I mean I think part of its things outsization, and part of it's like a language barrier, right, people are behind the bar and and aren't comfortable with English. I worked at a sushi restaurant for a little bit, and the chefs there were big sports fans, and so the only way they communicate with me was with uh sports words. So they say things like if they dropped something, they say fumble, or if

they need me, they'd call a time out. That's pretty great, but you know, the language barrier must make it pretty rough in a lot of cases. And that makes sense. And you know, it also seems true that Americans aren't too hung up on maintaining these Japanese sushi traditions. I mean, if you need proof of our lack of reverence, look no further than the sushi burrito, Yeah, or m the sushi croissant, the sushi cheeseburger, dessert, sushi, deep fried sushi roll.

I mean, I'd tried deep fried sushi roll. I'll be honest with you on that. In the list of sushi on and on and yeah, I guess they are technically combinations of sushi and other popular foods in the US, but I don't know. I'm thinking the more fitting word

is probably abominations. And that's certainly what the Japanese Ministry of Agriculture was say, and and the department has been not pleased at all to see these ridiculous places that we've taken Japan's beloved cuisine too, and so much so that they recently launched a new program that will actually certify whether Japanese restaurants outside the country are staying true to the values of traditional Japanese cooking. I mean, they're gonna have their work cut out for them. Oh no kidding.

I mean I was actually looking at this one article and according to NPR, there over eighty nine thousand Japanese restaurants outside of Japan, and about twenty two thousand of those are right here in the US. So this new program is going to review all these places, and and what like, are they gonna find these Japanese restaurants or shut them down? I mean, you know, it's not like

they have this international authority. So the program is completely voluntary, and the certification is basically this badge of honor for authentic Japanese restaurants, So it shows customers that this is a place to experience traditional cuisine and not these cultural mash ups like sushi burritos, and is one sushi chef put it. Don't get me wrong. The sushi burrito is a cool concept, and I wouldn't tell anyone not to eat it, but I wouldn't say it's Japanese food. I

mean that that's strong a line there. Yeah, I mean, like kim chi tacos are great, but spaghetti tacos aren't exactly. But while we're on the subject of different sushi experiences, do you know that Japanese people are actually better at eating seaweed than we are. I mean, they definitely have more experience. What don't mean they're better at it? Trash talking this. There was the study publish in Nature and and uh. It featured the work of these scientists who

were studying this marine bacteria that breaks down norri. It's really good at breaking it down. And that's the kind of seaweed that's most commonly found in sushi. And apparently the enzymes that cause this decay are also produced by bacteria that live inside some humans guts. So wait, so they only live in Japanese guts or what? Yeah, that's right, or at least they haven't been found in the guts

of North Americans. So you know, we have trillions of bacteria living in our intestines, and they account for hundreds of different species. But North Americans lack the one that produces this seaweed eating enzyme. That's pretty crazy. So do we know why that is? We're not sure, but there

are a few theories. So the main one is that Japanese people, you know, a long time ago, swallowed this enzyme along with some seaweed a while ago, and from there the enzyme genes were transferred to the microbes living in the person's gut and then handed down through the family bloodline, and the genes might have been phased out at some point along the way, except that Japanese people kept eating seaweed heavy diets. So why I get rid

of something that aids in digestion. That's pretty amazing. You know. I'm actually glad you brought this up because we've talked a bit about history, We've talked a little bit about culture, so I feel like we should take some time down and check out more of the surprising science behind sushi because there's some really interesting stuff there. Definitely, but let's take a quick break first. Okay, Well, so let's get

scientific wish sushi component do you want to look at first? Well, We've mentioned a few times now that mixing with savy with soy sauce is a bad idea, so I kind of want to break down why that is. But first let's be clear about what was sabi is and what it isn't. Because you know the spicy green lumps that are served in American restaurants, the one that mentioned my father in law eating, and you know, prepackaged in these

sushi trays, that's actually not was sabi. So real was sabi is made from the grated stems of a plant that's native to Japan, which means getting your hands on it outside the country can actually be really expensive. So I'd heard this, but I don't know the specifics. So what's the stuff we've been eating. Well, most of the wasabi here in the States, it's made from horse radish and mustard powder plus a little food coloring to give it that healthy green glow. And if you aren't being

charged separately for wasabi, it's most likely fake. That's interesting. But aside from like the cred in the kitchen, is there any advantage to using real with sabi? Well, it depends on who you ask, but real was sabia is said to have a more herbal taste than the fake

stuff that we're used to eating. And and because authentic was sabi loses much of its flavor after only fifteen minutes from being grated, the the sushi chef generally prepare a new batch for every single order, so you know, the real stuff has a much more fresh taste as well. That's crazy it loses its flavor so quickly. But I'm guessing neither kind should go in your soy sauce. No, definitely not, so I hope you hear that, Tristan. But you know, the reason really has more to do with

science than etiquette. So that pungent burning sensation that was sabi causes in our nasal passages, that that's due to a volatile chemical that it contains. Now, this chemical is similar to mustard oil, so it actually turns up in both real and fake was saby. And because with sabi's heat comes from a chemical rather than an oil based heat like chili peppers, for example, you know that that

burning sensation can be counteracted by food or water. So if you think about it, when people mix with sabi with water based soy sauce, they're really neutralizing that heat and and killing most of that natural flavor in the process. Yeah, it's really self defeating stuff. It actually reminds me of something I read that when sushi chef's notice people adding a ton of with sabi to their sushi, they immediately switched to less desirable cuts of fish, you know, the

stuff the kitchen needs to unload. And the thining is why waste all this premium fish on folks who are only gonna drown it with savvy anyway? Yeah, that's you know, it's it's a good point. And I mean, obviously, the big draw of sushi is the phenomenal taste of the fish, so you don't want to bury that in condiments and and spoil the whole effect. And by the way, have you ever stopped to think about how weird it is that we love the taste of raw fish so much.

I mean, it's like raw chicken, raw pork. We don't want any part of it, and obviously for good reasons helped, but raw fish, I mean, it feels like people are just obsessed with it. Yes, I was curious about that too, and I ended up checking out the work of this biophysicist. His name's Old morrits, and so, according to him, the

addicting taste of raw fish is actually thanks to gravity. Yeah, in the ocean, gravity's effect is so weak due to the buoyancy of water that most fish basically float weight sleep for their whole lives. And the result is this laid back lifestyle that the fish muscles are much softer and smoother than the you know, the thick ropey muscle fibers that terrestrial animals have, and and typically the more

work a muscle does, the tougher it grows. So I guess while fish are floating around without a care in the world, those of us on landers that were waging this constant war against gravity just to stay upright, I guess I didn't hadn't thought about it that way exactly. And that's why the fatty belly of the tuna is such a prize cut for sushi lovers. It gets the least used, so it's always the softest, tastiest part of

the fish. But you know, if you think about the muscle qualities of fish, they actually explain more than why sushi tastes delicious. They also account for why sushi looks delicious. And this was just fascinating to read up on. So, the rainbow colors of the fish used in sushi are mostly due to the amount of oxygen in their muscles. So when a more active fish, say like a tuna, you've got a protein called myoglobin that carries oxygen to

the muscles so they can make it into energy. But my globin also contains iron, which happens to take on that deep red color that you see in the fish. That's pretty cool. But what about something like a flounder though when I see those in restaurants there like, it often looks more white when used in sushi. Yeah, So that pearl white color and a fish, it indicates that there were maybe more sedentary and that its muscles didn't need that steady stream of oxygen in order to make energy.

So there are also lots of fish that have a combination of muscles that are oxygen dependent and ones that aren't, And as you might expect from those, those are fish that wind up looking, you know, maybe a little more pink. So, I mean, I guess that explains why salmon have that pinkish orangish color. Well, good guess, I know you're trying to be smart on that, but it did not exactly.

There are actually two things going on with salmon, and that that's depending on whether they're wild or farm raised. So in the wild, that trademark orange hue is derived from the fish's diet, not its muscles. So salmon are eating a lot of shrimp, a lot of krill, and and these are are shellfish that contain a certain pigment that's actually similar to the one in carrots that give

carrots that orange color. Well, well, what about raised SALMONA well, believe it or not, those salmon are actually artificially colored. And so salmon raised and captivity maybe they don't have the luxury of eating shrimp dinners. So so the fish farmers are actually adding a pigment in order to give

them that salmon color that you see. And it's it's not something that the farmers are actually all that excited to do, not just because they you know, they don't want to be adding something artificial, but also because it's expensive to do. I mean that they say that it costs as much as of their feed bill to add this pigment. That's crazy. But the public expects to see this rosy, pink and orange salmon and studies show that this is true. I mean that they're willing to pay

more for it. So, according to this market research that I was looking at, American consumers will pay as much as a dollar per pound more for that darker colored salmon that you see out there. I know I feel the same way like when I see eggs. I know, brown eggs aren't better for you than white eggs, but I still like the field and more. But obviously that's a lot of money to leave on the table or

something as trivial as color. That's true. But no matter what you think about dying fish pink, these newer methods are definitely a whole lot better than the old industry standard. I don't know if you've read about this before, but they used to slice the fish open and then gas it with carbon monoxide in order to change It's like, I swear, that is a real thing. It's gross. Yeah, I mean, I take the pigment compounds over then. I kidding.

But we've given fishing to do so I want to circle back to the science of sushi's other star, and that's the rice, because it's really as important as fresh quality fishes. It's the rice that makes or breaks a piece of sushi. And that's why sushi chefs are is so meticulous about which rice they use and how they cook it. All. Right, so what makes for good sushi rice? Well, most Japanese sushi chefs have they their own go to grains, which are sometimes the ones grown in their own hometowns.

But the real secret sushi rice is to find a short grain rice that can absorb a lot of water without cracking. And you have to see the the rice takes in water as it cooks, but if the grains absorbed too much, they'll actually burst open. And so what does that That like throws off the texture or something? Yeah, that's right, but it's not the cracks themselves that are

the problem. The real issue is that every grain of rice contains a bit of starch inside, so when it cracks during the cooking, the starch can leak out and that turns your rice into a mushy, sticky mess. And with sushi, you you definitely want to feel the texture of each grain as well as the air between them. So to sidestuff that problem, a good sushi chef will actually south their grains ahead of time and check for

cracks before using each piece of rice. I feel like sometimes I'm not tasting the right way because I can't say I've ever felt like I was tasting each grain of rice and the air and between the grains of rice. Well, I mean that portable shrine analogy makes a lot more say, yes, I get it, I understand it now, But I mean, actually, think about all this. It is amazing to see how much thought and care goes into crafting even you know, like a single piece of sushi. And I know the

rigor of preparing or even consuming sushi. It it can feel, you know, daunting or uninviting to someone who just wants to grab a bite to eat. But I do hope we've shown today that there's a real elegance and a logic to each in every sushi custom. And the end goal isn't to make you feel frustrated or uncultured, but really to give you one of the best food experiences

that you could have. Yeah, and and speaking of elegance and logic, we should probably get started on one of our own customs, unless, of course, you're threatened by its rigor. If you're talking about the fact off mango, I'm pretty sure I can handle it. I'm even willing to go first here. I've got a good one here. So it says if you want to go to the oldest and biggest fish market in the world, you'll head to Sukiji Fish Market in Tokyo. Now, one of the coolest things

I saw about this. This is their big tuna auction that happens regularly and the sushi stets go there to bid on bluefin. The auction starts at three in the mornings. You'll need to get there little bit after midnight to guarantee a seed, and then you can watch sushi chefs pay some seriously big bucks. I was looking at the numbers on this and the most ever paid for a blue fin at auction there was one point eight million

dollars for a single four eighty nine pound fish. Is that not the same I've never paid that much for a fish. I haven't even been to a fish auction. But it's being a blue fin. It might be a hot ticket item now, but fisherman actually used to avoid it, and that's because it's a really strong fish and it would tear up the fishing nets. But this all changed in the fifties because nylon nets came along and it became an easier to catch. But you know, sadly that's

resulted in over fishing. Yeah, and that's definitely a very big problem. All right. Now, we talked earlier about the Tokyo restaurant suki Yobashi Jiro that was made famous by the documentary Zero Dreams of Sushi, and it's often cited as the best sushi restaurant in the world. So I was looking at how you could possibly get reservations, and it's definitely not easy. First of all, you can only call on the very first day of the month. In

order to make reservations. You've got to be prepared to speak Japanese and leave a Japanese phone number behind just so you can hope to score a reservation. So do all those things, and it's a possibility. But you know, interestingly, there's no menu at the restaurant. It's just a twenty course meal made up of whatever Gero's in the mood to serve that day. And it's actually surprisingly quick meal.

They expect that each piece of sushi is going to be eaten as soon as it's presented, so so really it can take only like thirty minutes or so to eat this three hundred dollar meal. That's amazing. Do you know that there was a two thousand seventeen study that showed that nearly half of all the fish from well

respected sushi places in l A were mislabeled. Yeah. So the study actually looked at more than three fifty samples of ten fish and this was across twenty six really good restaurants, and what they found was that sent were fake. Yeah most of the time fish like red snapper or

yellow fin, we're actually a fish like flounder. Wow. Alright. Well, last year Seamless that the data on sushi orders across several major cities around the country, and it was kind of interesting to see that, you know, certain types of sushi are much more popular in certain cities than others. I was taking a look at this. In Boston, it's eight times more likely that people order spicy tuner rolls

than in other markets. Now, if you want a crunchy, spicy tuner roll, then you need to head to Denver if you want to be in what the popular pack there. In Miami there's seven times more likely to go for a salmon temporal role than in other cities. Of course, in Philly, which I know you're close to a deep fried tuna and salmon is the popular one there. And then in DC, the spicy crunch shrimp roll is thirty five times more likely to be ordered there than in

other markets. Why do they like that one so much? Times So, it seems like when we talk about sushi or other really fresh foods, people often talk about freezing those foods is a terrible thing. But this is something I learned in our research. Did you know that FDA regulations mandate that raw fish has to be frozen for a specified period of time to work can be served. I mean it's to kill parasites, and it applies no

matter how fresh the fish maybe. And in Japan, the real sushi masters know how to look for parasites or other problems with the fish so they can still serve the fish without freezing it. So every piece of fish that we eat in a restaurant here in the States, sushi or not, has to be frozen at some point before. Wow, I didn't know that. Actually this means that sushi is pretty much just like all those frozen fish sticks I used to eat as a kid, and that makes me

really happy. So I think for that I'm going to give you today's fact Off trophy. Congratulations Mango. Thank you so much, and if we forgot any great sushi facts, please don't hesitate to let us know. You can always email us where at part Time Genius at how stuff Works dot com, or you can call us on seven fact Hotline that's one eight four four pt Genius, or you can find us on Facebook or Twitter. Thank you

so much for listening, round, Thanks again for listening. Part Time Genius is a production of How Stuff Works and wouldn't be possible without several brilliant people who do the important things we couldn't even begin to understand. Tristan McNeil does the editing thing. Noel Brown made the theme song and does the MIXI MIXI sound thing. Jerry Rowland does the exact producer thing. Gave Bluesier is our lead researcher, with support from the research Army including Austin Thompson, Nolan

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