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Most sushi fish isn't fresh (medium.com)
150 points by iamwil on Oct 17, 2017 | hide | past | web | favorite | 127 comments

Flash-freezing is an entirely different beast than tossing something in your freezer. I wish we'd just embrace it culturally - the results are often much better than "fresh", and are far safer, longer-lasting, and more consistent.

I catch my own fish (other than sushi/sashimi I haven't bought fish in years) and 100% agree with you. You can taste the difference between fresh and frozen in a home freezer, but I think you wouldn't notice with flash freezing in a blind test.

And a lot of fish (kingfish and the rest of the seriola family for one example) are _better_ after a few days anyway, similar to resting beef.

If you're freezing your fish at home, put it in water. I clean them and put them in ziplock bags with just enough water to cover them.

I don't have a good word for this, so I will say that it removes the freezer taste.

Thanks! Will definitely try this. I invested in a vacuum sealer which works OK but is a bit of a pain.

My approach lately is to give away what I can't eat immediately.

Try a few methods in this link[1]. I’ve had great success with fresh fish using the water glaze. Lemon gelatin is supposedly the best method but I haven’t tried it myself.

Go Dawgs![1]http://nchfp.uga.edu/how/freeze/fish.html

Interesting - thanks for the link! I'll have to try these some time.

I do wonder how much of this is just preventing condensation / freezer burn though. A moderate ice layer will probably be enough to stop auto-defrosting freezers from destroying food so quickly.

You will probably get similar results with vacuum sealing your fish. Alternatively, you can try the water displacement method: https://anovaculinary.com/sous-vide-water-displacement-metho...


Ever go on vacation someplace famous for its seafood? Well, ask what seafood on the menu is from the region. You may be very surprised.

The trick to getting a truthful answer is to come across like you're just enthusiastic to have an authentic local dish. Then the manager or server is more likely to empathize and steer you towards what, if anything, is actually local. I've found that asking what is 'from the region' elicits better responses than asking what is 'local'.

I've also learned that when someone is admitting, by omission, that a lot of the fish and crustaceans on the menu are not local, they do not really want to explain where it's from. Usually its from all over the world and to know for sure they'd have to go look at a box in the alley.

Whenever I've visited to remote coastal towns, I've always been skeptical of freshness. Contemporary American food distribution is pretty much hub and spoke.

We're close with Michelin-star sushi chef and he's never tried to hide the fact that all of their fish has been frozen at some point. He finds it odd that diners care about it so much, but he's also of the opinion that all fish tastes better after it's been dead for at least a day. Certain fish even tastes best after a few days frozen.

There's a Parts Unknown episode with Anthony Bourdain where he highlights this, basically saying that if he ever hears anyone say "That sushi was so good, it was so fresh" he knows that don't know what they are talking about.


I don't know about typical sushi fish, but I've eaten a lot of cod that was caught, boiled, and put on the dinner table all within about forty minutes.

It falls apart on the plate, but it's also one of the best-tasting types of fish dinner I've ever had.

Once it's an hour old it's too late, though, so I don't expect to ever see such fish commercially.

Yup. At least several kinds of fish are really good fresh. There is this Cantonese thing with live fish that are killed and immediately cooked... usually steamed but also pan fried. Delicious.

There's at least one restaurant in San Francisco Chinatown that sells _live_ drunken shrimp. Yes, they're still moving, if only sporadically. It's a fun dish, but uncooked shrimp are pretty tasteless, and the rice wine doesn't help much.

Which place is this? I kind of want to try now.

Great Eastern on Jackson St. I don't know if you can order straight off the menu or if you need to clarify you want the live dish.

The first time we ordered it the shrimp weren't moving for several minutes, so we felt deflated and resigned to eating unexciting raw shrimp. Someone picked one up to eat it and let out a shriek when it jumped.

Thanks will give it a try!

You can keep the fish (and squid) alive, and even stir fry it alive. Won't work with all fish, obviously.

Mmm I havent had good "fresh" sushi as cooking rice takes time, sashimi on the other hand, I have had literally pulled from the ocean, cut and not even bled tuna straight off the chopping block on the back of the boat. Good stuff but a bit messy. Same goes for pearl meat, fresh straight from the shells is the best way to have it. Stuff is like butter. Post freezing the meat is still good, but not the same flavors or textures.

In Italy, it's actually mandated by law that raw fish needs to get frozen at least for a very short time before being served, as a precaution against anisakis.

That's the case across the EU.

Yeah if you've been to Tsukiji then you've likely seen frozen blocks of tuna being cut/packaged/shipped etc and this is really no surprise. The fish is caught so far away that there's no way you can get it "fresh".

It's all marketing and people having no clue what the food industry is like.

Most people have no idea how long most livestock has been dead before you get your cut of meat.

Same with produce. Your average imported produce has been in a temperature and gas concentration controlled container for months.

I highly recommend the book "The Sushi Economy: Globalization and the Making of a Modern Delicacy" by Sasha Issenber:


Its a fascinating read, the author spent 2 years traveling around the world from fishing boats, to wholesalers, to sushi restaurants following the supply chain.

Thanks for the tip, I'll check this one out.

This was news to me, but in the other direction: the claim is that 50-60 percent of fish served as sushi has been frozen at some point, implying that 40-50 has never been frozen.

Given that most of the non-tuna species need to be frozen and the tuna supply chain consists almost entirely of frozen fish outside of some high end restaurants in big cities (and perhaps some fishing towns that make a up vanishingly small portion of sushi consumption) - where is all this fresh fish coming from?

On top of that, salmon and varieties of tuna seem to make up the large majority of fish used in sushi. Yes, other options exist, especially at high-end places, but go into your run-of-the-mill sushi joint pretty much anywhere and those two dominate (not counting the "fake crab" that seems to make up half of maki by weight these days - that's certainly frozen also). As above, tuna is generally frozen, and salmon largely has to be, so where is all this fresh fish at?

Just because it hasn't been frozen doesn't mean that it is fresh either. Consider the number of smoked fish options (such as smoked salmon) -- the fish can be shipped refrigerated after smoking, and can last quite a while.

Enjoy your sushi while you can because at current fishing rates it will be gone in our lifetimes, fresh or frozen.


Surely that only means the price will rise to become an exotic delicacy, rather than "gone"?

Unless there is some kind of global control on catching, for example, blue-fin tuna (which travels outside of nationally controlled waters), "gone" seems more likely. The feedback loop of, the rarer the fish - the higher the price, will push some species to extinction in the wild.

I've never eaten sushi, so I'm not familiar with what fish are normally eaten, but can these fish be farm-raised?

Yes they can, they are farming a fish called Cobia in Queensland Australia that is a sashimi grade fish. The farming process is surprisingly good too, they worked with a local company and sorted out a crop based land grown food pellet for the fish to remove a large amount of reliance on pulling their food source from the ocean.


Farm raising tuna is difficult. Not sure if it is done commercially yet and, even if successful, I would guess wild caught tuna will still be highly prized in Japan. It is really the Japanese market that is and will keep driving the high end of the fish market.

It's a little more complicated than just 'farmed vs wild-caught', as a lot of tuna is wild-caught, then transferred to floating pens to fatten up for up to a year. Penned tuna are neither truly wild, nor considered farmed as there is no breeding stock.

Sure. You'd have to be pretty lucky to find a wild salmon in a sushi place - and if you did it'd probably be twice the price.

A somewhat recent development in packing fish is automated cutting and vacuum packing - alive to wrapped in less than 30 (or so) seconds.

This is afaik also being done on factory ships, with fish like cod. Still rather new (a few years?) and expensive - but a great way to treat fish. Many of the advantages of flash freezing without the down sides.

We've eaten things to extinction before, so no, don't assume anything.


I'm still hesitant to agree that we caused the mammoth extinction. There just weren't enough people at the time to do it with the technology we had, especially in places that lack enough cliffs.

We've had spears for quite a while now.


That's a remarkable list, thank you for sharing it.

The problem is that then it becomes more lucrative to harvest.

For example, the high price of tusk and horn isn't saving the elephants and rhinos.

Perhaps, but not necessarily. There are real concerns that with a combination of temperature rises, ocean acidification, and trophic cascades caused by overfishing, the oceans will entirely die in the medium term. They are certainly in the process of dying (like nearly all ecosystems under the assault of 'economic growth').

Your assuming population response is linear, it isn't. Passenger pigeon showed us that populations can collapse rapidly below certain thresholds.

Increasing the incentive to catch every last one, presumably?

as long as it isn't subsidized like the livestock industry.

I'm european and I prefer salmon sushi and it probably won't go away anytime soon. salmon is easy to farm and produce in masses.

The problem with farming salmon is that the food pellets salmons eat are made out of wild caught fish. Typically, for every kg of salmon you need 2kg of wild caught fish...so not really sustainable.

Current food-to-fish ratios are much closer to unity, usually 1.1 to 1.2.

The nice thing about inefficiencies such as this one is that the cost is not externalized, thus companies have a large incentive towards reducing the problem.

what is that ratio of the wild caught salmon?

Literally a rush to eat fresh water eel while supplies last as we speak. (That is stoked by even supermarkets in Japan... ~_~)

what about farmed fish though?

I was under the impression that farm raised fish (compare to natural fish) has the same problems as farm/cage raised chicken/beef/etc...which is excessive use of antibiotics.

But that is a different problem with different, feasible solutions. Farm raised fish are our what we will be eating in the future.

Plant-based and lab-grown is what we'll be eating in the future. Farms (be it livestock or fish) are inefficient and cruel.

> compare to natural fish

You mean compared to wild fish. Farm raised fish are still natural.

But in any case, even if there was a lot of antibiotic usage, the point still stands: There will not be a shortage of fish.

Uhm, well, given that 1kg farmed salmon needs 2kg wild caught fish, there may still be a shortage of fish...

Tilapia eat vegetation, you can use them for feed.

Why does the salmon feed need to be wild? Why can't it also be farmed?

This ignores history. Every time some resource became scarce people figured out a way to get more, or find something else.

Once prices go up, people will figure out how to farm tuna, and then they will no longer be scarce.

A single tuna can lay 6 million eggs. You don't need that many to supply the entire worlds demand for it.

Every time, really? Like every single time?


This kind of short-sighted hubris is why we are on the cusp of ecological collapse.

Parent commenter should have said "every time something becomes scarce and highly-valued," although I'm sure there are exceptions to that as well.

Passenger pigeons weren't really a resource and wikipedia page says they were mostly driven to extinction by deforestation for land use and lumber and fuel... which are resources.

Weren't a resource? How so? Why were they hunted then?

Yeah you're right, without market forces we never would have built those blue whale farms.


When blue whale blubber became scarce we .... switched to a new fuel. So that's actually confirmation of my point.

You're ignoring why it became scarce.

I asked a sushi chef about using local Pacific mackerel since I liked his saba. He said that his mackerel came from Norway and that he wouldn't use Pacific mackerel because of mercury levels.

I've eaten a ton of saba. He made great saba. But I can't eat it in most sushi restaurants because it isn't fresh. Now this article talks about the fish being fresh and that is one thing. Another is for something like saba which takes about 24 hours of preparation. Salting + marinating, there is differentiation in these. But when it's done, it's meant to be eaten. And if a restaurant doesn't get enough orders, it get put back in the fridge.

And that tastes like old stale fish. I suppose I should ask when they make it and come by that day.

BTW, my sushi chef closed his restaurant on University Ave and now caters mostly to startups. My ex-gf was also a chef and she told me that it's hard to make a living running a restaurant. It's much easier in catering since you know exactly how much to prepare on a day.


Good saba is hard to come by in the states. It's the one item I make sure to order at every sushi place I go to in Japan, because it's so hard to get a good one back home.

where is your favorite in the bay area?

Not really happy with any of them for various reasons so I'll cop out and say Shunji in LA. X_X

That being said I think plenty of places in SF offer high quality nigiri, and a few places in South bay are decent places for casual stops. None really entice me to frequent them.

I always found the cognitive dissonance interesting when people claim the best sushi is never frozen, while simultaneously ignoring the fact that even at places like Tsukiji Fish market, all the fish that is being offloaded from the boats is all obviously frozen.

In many places the 'best sushi' is not even legal. For example, EU regulations state that fish to be consumed raw must have been deep frozen (-20 C or lower) for at least 24 hours prior to consumption, to kill any potential parasites.

This also means you can never eat 'fresh sushi'.

After reading this story, I would never want any raw sushi:


Or any of these: 1. https://www.youtube.com/watch?v=V8_sF7kAnqY costco 2. https://www.youtube.com/watch?v=UM4RNIAnv5s costco (in store) 3. https://www.youtube.com/watch?v=QL9CVDEkDt0 4. https://www.youtube.com/watch?v=0yfJ88R2lI4 Flash-freezing is utterly essential, especially with present sea conditions; however, I don't eat any fish raw anymore, frozen nor fresh.

  > Raw farm-fed salmon and saltwater fish such as tuna are
  > generally safe to eat, 
I'm surprised by this. The amount of chemicals used to keep farmed fish free of parasites must be insane. I've never made sushi myself, but if I did I'd only use wild tuna as, AFAIU, it has the lowest parasite load.

At what point does fish cooling on ice become frozen?

I went to the tuna auction at Tsukiji a while back.. massive frozen tuna https://paulstamatiou.com/photos/japan/japan-day-5/

OT, but I had no idea tuna were that big.

This is the current average size of tuna now, from what I gather. The average size 50 years back was much bigger. In 1979 a guy caught a bluefin of around 1,500 lbs. Tuna are big fish.

I've known for a couple of years now that tuna are big but I grew up thinking tuna was a small sardine sized fish. It probably was due to the fact I never see whole tuna at fish markets (probably too big to sell the entire fish) and it comes canned.

Yep. And expensive. The value of the inventory in that room is probably on par with the average luxury car dealer.

Even more OT, but if you like sushi, the documentary Jiro Dreams of Sushi lightly touches on the entire process of making sushi in a Tokyo restaurant along with the story of a family restaurant. Then if you liked that, there is a touching and gentle mockumentary about it called Juan Likes Rice and Chicken.

LOL Some tuna are huge. My biggest was a little over 600 pounds. I didn't keep it. The captain, crew, and I sold it down in Portland, ME. We then partied with the money.

A very, very common misconception.

They're also incredibly fast (45mph), agile, and one of the apex predators of the ocean. They are also warm-blooded.

OT, as well, but this is a fantastic resource you've compiled, well done! My wife and I are finalizing our trip to Japan for 3 weeks this December and I am taking some notes based on your posts here for places that went past our radar!

There are plenty of fish in the market that aren't frozen. It seems you're only thinking of the tuna.

"Superfreezing is a relatively new technology that was developed in the 1990’s that drops the core temperature of a 500 pound tuna to minus 70 degrees below zero."

Found this part interesting. I worked for a short while in fisheries in the mid to late 90s, and graded fish for Sushi. There/then fish was iced, not frozen, as soon as captured to slow their metabolism, reduce any after-effects of stress, a cut is made so they also bleed, and die faster and as peacefully as possible. They are kept long enough to allow for rigor mortis (I guess what this article refers to aging), so when it ends it results in soft, melts-in-your-mouth meat. But no, not frozen, not for the "No. 1" destined for best clients. Lesser (cheaper) restaurants yes, frozen, older, lower quality fish.

This article refers to the US, and yes most of it is far, far away from the coast, and only way is to freeze it to distribute it such long distances. Unless flown in, obviously making the product much more expensive. So sure, as title says "Most sushi fish isn't fresh". In the same way, most sushi isn't the best sushi. And in many cases it doesn't really matter, if you want a quick and still yummy meal.

For tuna you can readily tell, even if you haven't trained your sense of smell, by the color. Most tuna here in the US you can see it a matte pink, instead of deep, alive, blood-like red, and you know right away it's been frozen.

Anyway, it seems to me the article gives the idea that freshness doesn't matter at all for sushi. I disagree.

For tuna, the color reflects the fat content. Maguro/akami ("red flesh") is red & lean, and stays that way even if frozen. Chutoro is pink & fattier, while otoro is light pink & extremely fatty. (It was fed to cats in the olden das, before tastes changed and it became an expensive delicacy.) Brown tuna has oxidised and you should steer clear of it, but this is not a common sight these days.

Also, essentially all commercially sold tuna has been flash-frozen, because it's caught in the deep ocean. That famous tuna auction in Tsukiji? All frozen, every last one.

FWIW, I've had locally caught, non-frozen tuna a couple of times. It's good, but while the texture is different, it's just firmer, not necessarily better.

Most tuna here in the US you can see it a matte pink, instead of deep, alive, blood-like red, and you know right away it's been frozen.

I thought it was red because it's treated with carbon monoxide? http://www.nytimes.com/2004/10/06/dining/tunas-red-glare-it-...

Some tuna actually is red, though. For example, yellow fin tuna. Caught one last month and when I got home my brother and I made sashimi... Meaning that we cut it into slices and ate it. It was so, so good. I still like it after it's been frozen, but it's no longer good for sashimi.

LOL yes, it seems they've found a way to game it. There's still the smell test, I hope. The point still stands, it's easy to tell by the pink color when tuna has been frozen.

"When butchered in this matter, the fish doesn’t know that it’s dead."

Otherwise it would know it's dead?

Your reaction was the same as mine initially, until I realized they meant that the fish's body doesn't respond as though it normally would once it's dead.

Yeah, I think it's related to something like this: http://mashable.com/2017/07/07/sliced-tuna-fish-flailing/#xe...

A somewhat more useful description would involve replacing “dead” with “dying” (though “know” is still a bit of a misleading term.)

The excerpt from Wikipedia quoted in the article is actually more useful than the article text on this point.

Lol, yeah, I thought the same thing. I assume the point is that the physiological reaction the fish has when dying is altered.

Interesting related fact that salmon sushi is a recent invention by norwegians and is not served in traditional restaurants in Japan - http://www.npr.org/2015/09/18/441530790/how-the-desperate-no...

I was in Kauai about 10 years back and a friend of ours who hunts goats traded with a friend for some fresh of the boat tuna. We tried a bit of that tuna the first day, maybe 8 hours after it was caught, sashimi style. It was terrible, just as our friend told us it'd be. It was super chewy and tough. Next night the stuff was great, and two nights later it was FANTASTIC!

I can confirm that it tastes best when you wait. I occasionally go Ahi fishing off the shore of Kauai with friends, and they usually ice it right away and wait a couple of days before cutting it for sashimi.

If it tastes good and doesn't make you sick, who cares?

OP here. A couple angles to this.

1) Anything is interesting if you look deep enough. What's frivolous to some is a hobby to another. Look at fanfic writers on the internet.

2) There are some things that we eat that have long term ramifications, rather than short term ramifications. Knowing what we put into our body helps us with the long term ramifications.

3) When it comes to sushi, it's pretty expensive, so you'll want to know what you're getting for the price. Learning more about it is one way to enjoy it as you're stuffing it into your face hole.

That was my reaction. But it's actually just a poorly chosen title. In fact the article basically says that freshness is actually not important in sushi

"Maguro and toro needs at least a week of aging, sometimes up to two weeks in refrigeration. Sake (salmon) and Ohyou (halibut) requires around five days of aging. On the other hand, according to Kaz Matsune, fish like binna maguro (albacore tuna) and katsuo (bonito) taste better without aging."

The amount you age the fish is important.

> ...who cares?

I know it was rhetorical but I'd assume vegetarians, conservationists, anyone concerned with overfishing, people concerned with the destruction of the ocean ecosystems.

My understanding is that all "sushi-grade" fish is previously frozen. The freezing process is apparently necessary to kill/remove parasites in certain fish breeds.

I think here in Massachusetts, at least, there is regulation to the effect that fish sold to be served raw _must_ be frozen to kill parasites. Possibly it is species-dependent, but I would make a guess that it is not.

PS: turns out it is somewhat species dependent:


This is true for some but not all species. Most fishmongers will not recommend eating salmon raw unless it has been deep frozen (and not just frozen in a typical residential freezer, which doesn't get cold enough), but most consider eating raw never-frozen tuna to be fine.

As with most things in life, it's really a question of risk and trade-offs. Parasites are rare enough in tuna that they are below the risk threshold for most people. Salmon less so, though it depends on where you get it and how much you trust them.

The broad guideline is that deep, open water, fast-moving fish have a lower parasite load than fish who live closer to shore, closer to the bottom, and/or don't move as fast.

Thus, tuna is pretty safe. But you're gonna want to cook an eel or a catfish before you stick it in your mouth.

One of the things I find fascinating about sushi but try not to think about too much, is that the clear implication is that all of the needed-to-be-frozen sushi I have eaten probably did have some parasites in it. I just ate dead parasites, which I admit is better than eating live ones. Safe, but still kind of gross.

A little off topic, but virtually all cigars imported into the US are frozen as well, usually by the distributors (there are a few companies who manage their own distribution who do not... like My Father / Tatuaje). This is to kill the tobacco beetle eggs that may be on the leaf. The exporters from Cuba also freeze their cigars before sale, but the cigars sold on the island itself (either name brands or custom rolls) are not. These beetles can cause thousands of dollars worth of damage very quickly.

There's actually no such thing as "sushi-grade" fish.

There is no standard or regulation that designates fish as "sushi-grade." It's a popular misconception.

I always thought it was a marketing term, where a certain store is willing to say “we’re confident that this can be eaten raw” and not some legal or regulatory standard of quality or freshness—that is, I thought the idea that it’s a popular misconception was itself a popular misconception. Moreover, I’ve even heard it used to describe simply “species of fish that are commonly considered safe to eat raw”.

I recently learned that “sushi-grade” is just a marketing term that has no meaning beyond simply “good grade”. It’s most often used by restaurants themselves. It’s not regulated or oficially defined in any way.

The article goes into some detail about the circumstances in which this is and isn't true (it's true for some fish from sources.)

Some of the poke places in LA use fresh tuna that was flown in from Hawaii. I think even the Costco poke is fresh. For those not familiar with poke, its a raw tuna , soy sauce and seaweed dish. You can remove parasites by sight easily.

> You can remove parasites by sight easily.

I'd rephrase that as being able to spot fully grown parasites easily, but parasites don't always come fully mature.

I believe this is only necessary for salmon. Because they spawn inland they host parasites whose life cycle includes terrestrial animals, like bears and humans.

> whose life cycle includes terrestrial animals, like bears and humans.

I don't think that's generally the case. As far as I know, the main salmon parasites that we care about are Anisakis (nematodes) and Diphyllobothrium (tapeworms). The former is much more common than the latter, especially in the US where as far as I know broad tapeworm has only recently been detected in a small fraction of Alaskan salmon.

Anisakis has no terrestrial hosts. Its lifecycle is crustacean -> fish -> aquatic mammal (whales, dolphins, seals) -> repeat.

Humans and other land mammals are the host of Diphyllobothrium, but, again, I don't think that's very common. From what I've read, most of the need to freeze salmon comes from wanting to deal with roundworms.

Can host both types of parasites in fact. Killer whales and marine birds are another typical predators.

Pretty sure all fish has parasites. I’ve read that chefs say all fish have worms.

Another surprise: French macarons are often frozen prior to display in patisseries. A French chef told me this was a professional secret. The Bouchon cookbook says it makes them "chewier and more fun"[1].

[1] https://cooking.stackexchange.com/questions/30892/freezing-b...

In France it’s forbidden to sell fish for raw consumption that has not been frozen at some point.

We used to eat shellfish at least "while it's still smiling" - caught right off the side of the boat, force the shell open with a knife, perhaps a dab of hot sauce, then down the hatch!

It's certainly a unique experience.

I wonder if this is the case with Salmon. I always find fresh wild caught salmon much better during the summer, than the flash frozen stuff. Could be due to the lower fat content in sockeye.

Salmon sushi is actually a modern invention; the result of the Norway government having too much fish in the 80s and needing someone to buy it.


According to what I found out, Salmon is prone to parasites, so it's often frozen to kill them.

I think there are two very different definitions of fresh causing confusion. I've seen US supermarkets keep fish on display for like a week, at which point it develops a very off "fishy" odor. I don't even think it occurs to the Japanese that anyone would do this, or they would be horrified to find out, but when Americans talk about fresh sushi they probably mostly mean sushi NOT having the nasty off flavors.

You rarely hear "that was a great burger, so fresh" because we don't have such a quality control problem with beef (as far as I know).

Go vegan :D

Unless you live in a coastal area and know a fisherman personally, all the fish you are eating -- whether from a fish-monger or your grocery store, has been previously frozen and thawed.

My friend was neighbors with a fisherman in Cape Cod. Now THAT was fresh fish.

Which is a good thing, if you're interested in not getting parasites!

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