Freezing salmon

Hey all,

I typically vacuum pack and freeze the fish that I don't eat w/in the first couple days of harvest. With my first big chinook this year I decided to take it a bit farther -- I bought some dry ice, crushed it, and mixed it into 99% rubbing alcohol, and used this mixture to flash freeze the vacuum packed salmon. Thing is -- it looks kinda weird... it turned white? See the photo, attached. Flash frozen fish on the left, regular frozen fish on the right.

I guess my main questions are:
(1) Did I mess up the salmon that I flash froze?
(2) Does anyone else flash freeze? I was hoping it'd preserve the texture better.

Thanks!

rubbing alcohol is poisonous. But I just realized you may have used it outside the bag.

iggie

You may have accidentally burned the meat a little bit by being too cold.  But, it should be fine, at least under the surface. 

A disadvantage of the dry ice/rubbing alcohol freezing method is that you'd have to buy dry ice and rubbing alcohol each time you want to freeze some fish, which is inconvenient and expensive.  If your freezer gets down to 0 degrees F, you'll get quite satisfactory results if you lay each vacuum packed fillet out separately so it will get down to zero degrees quickly. In other words, don't stack them in a pile when you're freezing them.

I used a suction style vacuum packer for many years for freezing fish, game meat, and produce, and was happy with the results.  But another way to improve the quality of your frozen fish is to buy a chamber vacuum packer, which does a better job of getting air out of vacuum bags than suction style vacuum packers.  However, chamber vacuum packers are large, heavy, and expensive. A lot more expensive than dry ice and rubbing alcohol! I store mine on a cart with all of my vacuum packing supplies, so I don't blow my back out when moving it to and from my kitchen.

Another DIY option that I've used before is to put a bucket of salt saturated water in the freezer.  It will get to freezing temps but not freeze.  Drop your vacuum packed fish in it.  Heat transfer happens faster to a liquid than to air, thermodynamics being what it is.

-Allen

Might be slightly off topic but what are the benefits of flash freezing compared to just vac sealing and freezing the conventional way?

A disadvantage of the dry ice/rubbing alcohol freezing method is that you'd have to buy dry ice and rubbing alcohol each time you want to freeze some fish, which is inconvenient and expensive.  If your freezer gets down to 0 degrees F, you'll get quite satisfactory results if you lay each vacuum packed fillet out separately so it will get down to zero degrees quickly. In other words, don't stack them in a pile when you're freezing them.

I used a suction style vacuum packer for many years for freezing fish, game meat, and produce, and was happy with the results.  But another way to improve the quality of your frozen fish is to buy a chamber vacuum packer, which does a better job of getting air out of vacuum bags than suction style vacuum packers.  However, chamber vacuum packers are large, heavy, and expensive. A lot more expensive than dry ice and rubbing alcohol! I store mine on a cart with all of my vacuum packing supplies, so I don't blow my back out when moving it around.

Which Vacmaster do you use?  Would you go larger or smaller if you could repurchase?

Might be slightly off topic but what are the benefits of flash freezing compared to just vac sealing and freezing the conventional way?

The benefits of fast freezing begins at the macro level when ice crystals begin forming in the item being frozen.

When you just dump any packaged food in your freezer and let nature take its course with a slow progression of chilling the item to the level it starts to freeze, the ICE CRYSTALS grow very long inside each cellular membrane. These "spears" will penetrate the cell membrane and perforate the cell. When the item is thawed for use, a lot of the moisture in the cells will weep out of the food giving it a drier, even tougher texture. Some of the flavor also is lost in those juices and moisture that leaves the food during preparation for eating.

Fast Freezing has the benefit of creating ice crystals that are very small and short with little time to 'grow' long enough to perforate the cellular membrane. Therefore when you thaw the item, the original moisture content is retained....along with the captured flavor and freshness too.

Here is a 5 paragraph abbreviated article from the Library of Congress crediting Clarence Birdseye for "discovering" quick freezing's benefits in preserving fruit, vegetables and meat for longer periods of time without deterioration of the quality and taste. He filed 168 patents over the years perfecting the process and packaging. You will be amused at how he actually come about learning the benefits of fast freezing.

https://www.loc.gov/everyday-mysteries/technology/item/who-invented-frozen-food/

As Paul Harvey would say: And now you know the rest of the story.  LOL

I've had fish that was flash frozen before, but honestly I never felt the need to flash freeze myself as I think it turns out just as well when you vacuum seal normally using a quality sealer, it usually preserves it for at least a year, more than enough time to go through my stock (I try to eat all last years salmon before I catch my first one for the year) texture has always been fine for me. A few tips I picked up from someone much older (not necessarily wiser) than me that I usually follow.

After you filet your salmon it DO NO RINSE it at all. Use a paper towel if you feel the need to get something off. Save the rinsing until just before you cook it.
Seal the filets 2 halves in a bag, meat-touching-meat (skin sides touching the bag)
Do not remove pin bones prior to freezing, wait until after it's thawed
If all of the air doesn't get out, try again or eat those ones within a month.

A disadvantage of the dry ice/rubbing alcohol freezing method is that you'd have to buy dry ice and rubbing alcohol each time you want to freeze some fish, which is inconvenient and expensive.  If your freezer gets down to 0 degrees F, you'll get quite satisfactory results if you lay each vacuum packed fillet out separately so it will get down to zero degrees quickly. In other words, don't stack them in a pile when you're freezing them.

I used a suction style vacuum packer for many years for freezing fish, game meat, and produce, and was happy with the results.  But another way to improve the quality of your frozen fish is to buy a chamber vacuum packer, which does a better job of getting air out of vacuum bags than suction style vacuum packers.  However, chamber vacuum packers are large, heavy, and expensive. A lot more expensive than dry ice and rubbing alcohol! I store mine on a cart with all of my vacuum packing supplies, so I don't blow my back out when moving it around.

Which Vacmaster do you use?  Would you go larger or smaller if you could repurchase?

I vacuum pack a lot of fish, game, and produce, but I don't pack commercial quantities.  I have a Vacmaster VP210, which is a good size for me.  If you want to be able to vacuum pack multiple bags at the same time, you'll need a commercial vacuum packer, which are really big and really expensive.

If you're tired of processing all of the fish which you catch, here's what you can put on your Christmas wish list: a fish filleting machine.  The Confederated Salish and Kootenai Tribes use this machine to fillet the lake trout turned in to them during the Mack Days on Flathead Lake, and fish which they catch in their efforts to reduce the lake trout population on Flathead Lake.  They give the fish to food banks and Tribal members, and sell them to grocery stores.  You can buy vacuum packed and frozen Flathead Lake lake trout for about $12 a pound at some grocery stores around Montana.

rubbing alcohol is poisonous. But I just realized you may have used it outside the bag.

Also flammable... which I remembered as I held the lighter in my hand, standing over the solution, seconds away from seeing whether the CO2 fumes would extinguish the flame. That coulda gone sideways real quick.

You may have accidentally burned the meat a little bit by being too cold.  But, it should be fine, at least under the surface. 

Dang, yeah, that was a fear in the back of my head. A google search for "flash freeze too cold" didn't turn up anything, but... I'm afraid you might be right. Live, learn, and in this case absolutely apply past learnings to future actions... maybe that 8lbs of steaks will be blackened a la Prudhomme. Ugh.

All others: Thanks for the alternative ideas and ensuing discussion. Made my day richer. The dry ice was a bit spendy, but it's pretty rare that I catch a 13 or 14lb gutted & gilled fish. Will probably try again but use a saline solution and less dry ice... target somewhere around -10F. Should freeze pretty quick. Will report back....