> After all, key to good sushi and sashimi is in ageing the fish, allowing the enzymes to break down and moisture to evaporate, resulting in a concentrated flavour.
Can someone elaborate / explain? I always thought that the main quality in sushi and sashimi fish is its freshness. The fresher the better, to the point where shops might even keep the fish alive in aquariums.
I think there is a sweet spot of age if, I think 4 to 7 days (frozen), otherwise for many sushi eaters it’s too bland. The freshness = quality is something pushed by restauranteurs taking advantage of people’s naïveté regarding sushi and sashimi.
Incidentally, one of the first things which made Japan-US flights viable (back in the ealy '70s [1]) was packing the cargo holds with frozen fish meant for sushi restaurants, from catch to restaurant took about 3 days which made it fit nicely, time wise.
Fish used in sushi is almost inevitably frozen, or you’d have a mouthful of extremely rubbery, almost crunchy fish. Remember also that the original sushi was fish fermented in salted rice for a while. As the availability and taste for fresher fish grew, along with modern refrigeration it was discovered that you get a better texture with fish that had been frozen immediately after slaughter.
This, it is important to note, is only really the case with large, slow-growing pelagic fish like tuna.
Freezing also kills some potentially zoonotic parasites that may be present in fish.
Unless you're buying it straight off the docks, or pulling it out of the water yourself, any unfrozen fish you see has likely been thawed on site, after delivery.
"Fresh" fish means that it was frozen on the boat, and just thawed today.
I sometimes make nigiri sushi by sawing slices off of a frozen fish filet with a kitchen-use-only coping saw. Then I put it in the fridge for the next day. Comes out fine. If I wanted, I could freeze the rice with it, and have sushi later in the week.
I have had sushi that was completely fresh — literally a tuna I caught myself, carried off the boat, cut up and ate. The taste and texture was fantastic.
You are right that almost all fish you eat has been frozen. This is partially for practical reasons: fishing boats are often at sea for weeks at a time. Also for safety reasons: most fish have a significant risk of parasites which are killed by deep freezing.
Tuna is one of the few fish safe enough to eat fresh and raw (and even then there is some amount of risk).
Also, most fish used for sushi are those that a generally less likely to have parasites that harm humans ( like tuna for example ). Wild fish like salmon, cod, etc are rife with parasites. The japanese historically never used salmon for sushi until farmed salmon became available. Farmed salmon do not have parasites because their feed is controlled - similar to how modern cows, pigs, etc do not have parasites as a result of farms controlling their feed.
People love to attack farmed fish, beef, pork, etc as being unhealthy, but they don't realize that farmed meat has helped wipe out a significant portion of harmful parasites from the west.
Consider it’s frozen (sometimes more than once) to kill parasites anyone claiming to taste freshness, beyond spoil, from one restaurant to another is to be taken with a grain of salt.
This. All sushi grade fish (in America at least) has been frozen at least once. I've actually heard people say "I don't eat sushi unless I can see the ocean."
Like they somehow believe that the restaurant employees are just walking down to the beach and plucking fish right out of the water.
You can be in the middle of no-where, hundreds of miles from the nearest bit of salt water, and the fish will be exactly as fresh as the sushi you would get on a beachfront restaurant.
Access to fish markets and sell-through rates are more important than proximity to an ocean. But places near oceans tend to place more importance on seafood, so they probably have better markets.
>But places near oceans tend to place more importance on seafood
Yeah, $10 fish and chips sold for $20 tourist trap restaurant that would be out of business anywhere else maybe.
I grew up near the ocean where fishing was the #2 industry behind tourism (if you ignore all the trades that support the tourism industry). I know how that sausage is made.
I'd rather eat prepared seafood in Des Moines. At least there the relationship between what you pay and what you get will be more consistent.
>Access to fish markets and sell-through rates are more important than proximity to an ocean
Yeah but interior sushi restaurants aren't picking out the fish themselves like nicer places on the coast, just ordering in bulk through some wholesaler/fishmonger
The fish in the middle of no-where might be just as fresh but also has a pretty ceiling for fish quality
I believe all of the best sushi places in Japan have their own ideal "recipe" for serving fish, and none of it is fresh. Flavor and textures start maturing in fish as the initial stages of fermentation start, much like how the flavor of bread changes the longer it has time to slowly prove.
“There isn’t much difference when we cook a fish with and without ike jime on the first day itself when it’s still fresh,” [chef Dannel Krishnan] explains. “The difference comes in only in the third, fourth and fifth day of aging. The fish that’s prepared by ike jime is still firm, and the flesh is pearly. The one that’s not becomes mushy.”
I always thought that the main quality in sushi and sashimi fish is its freshness.
Nope, not to people who eat a lot of sushi. The point is for the fish to be aged for the correct amount of time to get the correct flavour. The longer it is aged, the stronger the flavour will be, to a point where it is unpleasant. Different people will have different tastes, if you don't eat a lot of sushi, you will probably like it not as strong.
The restaurant wants the fish as fresh as possible, so it has the most control over the ageing process.
There are types of seafood best eaten fresh, and there might be some sushi I'm not aware of like that, but almost always it needs to be aged properly.
Freshly killed fish has weak flavor than aged. I think some people equate aged -> more fishiness, but this is only true up until certain point for poorly prepared fish.
I say that most sushi restaurants in N America go by using sushi grade fish that was probably processed by a fish monger, not the chef.
Aging fish really comes into play for high end sushi, where the chef is after some chemical reactions can only happen over time, it's not rot, it's more like it had time to rest and develop flavors that it would not have had if it was just straight from the fish right after it was caught.
Sushi dates back to before the invention of the fridge. It originated as a series of techniques to preserve fish. Sushi with fresh fish is a relatively modern take on it.
Old style sushi is sometimes called edomae style sushi, and it used various ways of preserving fish such as salt curing, ageing, smoking, braising and whatnot, all to extend the shelf life.
Can someone elaborate / explain? I always thought that the main quality in sushi and sashimi fish is its freshness. The fresher the better, to the point where shops might even keep the fish alive in aquariums.