What health benefits can be lost from freezing?

Exactly

Agree 100%. In the case of the sashimi grade stuff whenever we order we buy some fresh and some frozen for later. There is a difference but not as much as one would think. We're inland so at our local supermarkets etc, we always buy the flash frozen fish (for cooking, that is.) Most of the stuff at the fish counters has been frozen and thawed by them anyway and who knows how it's been handled. When you buy frozen you cut out that variable.

When I visited Tsukiji in August one of our escorts was reading off some of the details on the boxes of fish that were near us. Many of the boxes of frozen tuna were from January according to him. Just because it is frozen doesn't mean it tastes bad!

that's 2 things. 1) frozen tuna were bought from different places from atlantic (Spain/portugal are a few importers) for the mass market - think of the many restaurants in japan, how many tunas they need all tgt.

2) The fresh tuna are way more expensive and they are catered for the higher end restaus. some restaurants in HK even fly them in unfrozen from Tsukiji mkt.

that copper river samon that is flown hear from alaska is flash frozen and thawed? the sword fish i buy at harris teeter for a 50% premium that they sell as "FRESH FISH" is really frozen and thawed in the closet? the fish i buy at the fish market, has been frozen, and then flash thawed before putting those slimey devils on the table in ice to sell?

Since those are probably not intended for raw or undercooked consumption, they don't have to be frozen.

If they were being sold to be consumed raw, then yes, they would have to have been frozen.

Now if you buy that sword fish and salmon and make chiviche or something out of it it's up to you if you want to freeze it for the recommended periods or not or take the risk of the parasites.

Not quite true. I had meat sashimi in Japan. Wasn't sure if I could, but was nice in the end. Very very very rare steak

I do think freezing affects the texture of fish, but that could be a preconception, because I cannot say with 100% certainty what sashimi I have had which has been frozen or which has been not.

Freezing can affect the texture of fish. With some, you can definitely tell. A fish that is super frozen once (with a proper seal) and kept at that temp until a proper thaw should be nearly undetectable for certain fish. The problem with a lot of frozen fish is that it is frozen at an improper rate, subject to varying temps and possible likely slight thaw and re-freeze along the way, and then, finally receives a final thaw prior to sale.

After getting familiar with the restaurant scene in China, I tend to agree with the US government. There are a few countries in the World like Japan and partially Korea where you can mostly trust restaurateurs, but better to stay on the safe side for the rest of us.

You left out the "horse" in horse meat sashimi.

I've been tempted to fish for salmon near our place in WA and use the salmon for sashimi and un-pickled Ikura - but was warned against trying it due to the almost assured risk of picking up any number of nasty parasites that could end up causing serious problems.

Frankly, I probably wouldn't be able to tell the difference between flash-frozen and just caught anyway - although the Ikura part was tempting...I hate the mushy, drippy Ikura (salmon roe) some of the restaurants serve. I want it cool, fresh and almost bursting in the mouth as you bite.

I do know that if fish is served raw and unfrozen in Japan it has to consumed during the day after the night it was caught. It cannot be held over raw till the next day.

I can see how that might reduce the risk of some sort of bacterial nastiness, but how does that resolve the parasite issue? If they're there, they're there - whether the fish is swimming in the ocean (or where ever) or sitting overnight, unfrozen on some ice or in some fridge.

if there are "bad" parasites in some fish, what are these parasites? surely science has names, other than worms and bugs for them. what is a parasite. name bad parasites. i do know that some warm water fish, particularly the large ones, are thought to have parasites that are not good.

but this is nonsense . fish make up a reasonable percentage of the american foodstuff, and we describe the problems as "worms and parasites". and they are bad!!! what are these thingies in the fishies? we spend a billion bucks to flash freeze and thaw all the fish. why? let's not talk to medical science, let's find a real science that can tell us what horrible posioning fish freezing is stopping.

Not sure why this is so hard to understand. We don't flash freeze "all the fish". We freeze all the fish that is going to be eaten raw for a specified time at a specified temperature to kill the parasites that can make you sick. Fish that is going to be cooked does not need to be treated, as the cooking will kill them.

What are they trying to prevent? A partial list:


Anisakis simplex (herring worm)
Diphyllobothrium latum
salmon tapeworm (they grow to nine feet long)
Vibrio species (bacteria)
Vibrio vulnificus
Eustrongylides,
Pseudoterronova decipiens
Gnathostoma sp
Capillaria Phillippinensis
Clonorchis sinensis
Opistorchis viverrini
Metagonimus yokogawai
Paragonimus

To name a few. The most common are the first three

If you are really interested, googling will give more details, pictures, infection rates, etc.