Help. How to preserve a sashimi grade tuna

[Lori08]

Help.. I have bought a whole sashimi grade yellowfin tuna from a fisherman fresh from catch (already bled, gutted properly and stored in slush ice).
I'd like to know the proper way of storing the tuna to preserve its freshness and still be Class A sashimi grade that can be eaten raw. Is it advisable to store the tuna in a freezer and for how long a period of time? cause im afraid if i store it in a freezer it will degrade the quality of the tuna.

[BuonaForTuna]

First of all I wouldnt post that you bought a fish from a fisherman straight off the boat unless it was a commercial boat, and if that was the case be more specific because thats a nono and will cause a few eyebrows to raise. Not judging just saying. Anyways if it was sushi grade or not if its already cleaned up for you and ready to go you can always vacuum seal the fish and store it away in the freezer if done properly it will avoid freezer burn and will last over a years time. You can always use that same fish at anytime in that year and it will be just as good as it was the day you stored it.

[M/V Santa Rosa]

It will not hold its color unless it is CO2 treated like a block of Saku tuna.

It will not be of sushi grade unless your frezzer can hold 50 degess below ZERO.

After cutting the air will start to oxodize (SP)this cut of fish, during that time, the color will start to darken, you may wish to remove the bloodline from this cut.

In order to hold a true sushi value type cut, (In my opinon and it dont mean crap cause i,m so LOW WATTAGE) your frezzer really needs to be a deep frezze which can hold at 50 below or better.

If your frezzer can hold deep, then loin it out and toss it in the box, dont wrap it up or anything..

Ask Ali about the number one grade toro he ate from us here, taken from the deep frezze, not wrapped or anything. Just number one grade Blue Fin Tuna toro..

[fishnfool]

Jesse...Lori is in the Phillipines. Reading comprehension...attention to detail. Lori...listen to Tommy...he is in the biz, and knows his fish. If you can't freeze it to -50 try to vacuum seal it, and like Jesse said it will stay good for up to a year. Not as good as fresh but good.

[BuonaForTuna]

i saw that portion of it Kevan way before I posted. I was in Germany for a bit on here and it said glendale so you never know. Either way having said that it was to keep the member from get the dogpile.

[BuonaForTuna]

Originally Posted by M/V Santa Rosa

It will not hold its color unless it is CO2 treated like a block of Saku tuna.

It will not be of sushi grade unless your frezzer can hold 50 degess below ZERO.

After cutting the air will start to oxodize (SP)this cut of fish, during that time, the color will start to darken, you may wish to remove the bloodline from this cut.

In order to hold a true sushi value type cut, (In my opinon and it dont mean crap cause i,m so LOW WATTAGE) your frezzer really needs to be a deep frezze which can hold at 50 below or better.

If your frezzer can hold deep, then loin it out and toss it in the box, dont wrap it up or anything..

Ask Ali about the number one grade toro he ate from us here, taken from the deep frezze, not wrapped or anything. Just number one grade Blue Fin Tuna toro..

So the loin isnt Vac sealed? Just straight to the freezer?

[Lori08]

What if i will not freeze the fresh tuna catch how long do you think the tuna will stay fresh sushi grade in ice after bleeding and gutting? cause iv read the thread 'onboard handling of sashimi grade tuna' it said there that it can last upto 1 week, is it true?

Thanks for the advice this forum is very helpful.

[DenisB]

Depends entirely on how well the fish was really handled at capture & until you got it.

portions in domestic fridge ..............risky as sushi after 2-4 days ( average storage temp (say) +5 Deg C ).

whole fish in ice ................10 + days ( from CAPTURE date)
( storage temp approx 0 Deg c )

vacuum packed portions in domestic freezer................. month or two.
( storage temp approx -18 Deg C )

storage in -50 Deg C specialised freezer .............couple of years.

three primary issues exist with storing tuna for sashimi/sushi;-
1. - bacteria growth ( off flavours & health issues)
2. - fat oxidation ( off flavours)
3. - flesh texture ( ice crystal growth causing soggy, watery flesh on thawing ).

1. life is extended with cleanliness , vacuum packing to reduce access to oxygen & best of all gasflushing prior to vacuum packing to remove any oxygen at all.

2. is dealt with by the same practices as 1.

3. the critical issue here is minimising the time taken to get the core of the portion thru the temp range -2 Deg to -8 Deg C.............the faster the tuna gets thru this phase the smaller the ice crystals formed in freezing & the firmer the texture on thawing.
Domestic freezers are not great for fast freezing times.
( tips on domestic freezing practice have been provided before .......... ie placing portions to be frozen around the edges of the freezer in a single layer nearest the refrigerant coils).

if you want extended storage times & a high quality result it is best to use a commercial packing operation with gas flushing and commercial freezing equipment with the refrigeration capacity for fast freezing times.

one trick for extending fresh storage time of quality sushi/sashimi is to use a small domestic chest freezer & turn the thermostat back to hold at (say) -4 Deg Centigrade.
The salt content of the flesh will not allow the water in the flesh to freeze at that temp & the tuna stays firm, but not frozen..............and at the lowest temp to minimise bacteria growth.
this keeps the fish at a lower temp than storing in ice & avoids issues associated with melt water from the ice.
have only one cut face & seal the cut face with a plastic sheet during storage to minimise oxygen access to the flesh during storage.

Take care.................enjoy.

[http404]

Originally Posted by BuonaForTuna

i saw that portion of it Kevan way before I posted. I was in Germany for a bit on here and it said glendale so you never know. Either way having said that it was to keep the member from get the dogpile.

That makes a lot of sense.

Think before you post.

[M/V Santa Rosa]

Originally Posted by BuonaForTuna

So the loin isnt Vac sealed? Just straight to the freezer?

t the fish is slabbed out.
then blast frozen
then band sawed into 1pound strips. Like 3/4 inch wide by 14 inch long
and 4 inch tall or so,, give or take

then just tossed into the deep frezze,, sold at wholesale pricing of 68.00 a pound, true toro number one grade frozen.. give or take a few bucks

[babachu]

when you clean your fish with the intent to freeze it, rinse only in salt water. the clorine in tap water ruins the taste over time in the freezer. you can rinse it when you cook it.

[Professor]

Originally Posted by M/V Santa Rosa

t the fish is slabbed out.
then blast frozen
then band sawed into 1pound strips. Like 3/4 inch wide by 14 inch long
and 4 inch tall or so,, give or take

then just tossed into the deep frezze,, sold at wholesale pricing of 68.00 a pound, true toro number one grade frozen.. give or take a few bucks

Your feeding $68 a pound fish to Ali? Talk about over the top. He didn't put Unibutter on it did he?