Frozen Salmon: thaw Q and safe to SV?

NDG

Why does the vac seal on frozen fish always say to remove packaging THEN thaw?  I am considering SV for these - seems so wasteful to remove this vac seal only to vac seal again.  what if I just keep frozen in original vac seal, then toss direct into SV?  

GrateEggspectations

I’ve debated this issue myself in the past. Seems a shame to cut away perfectly good packaging only to repackage. Sous viding from frozen is no issue. I think the only thing that might give me some pause is the safety of SV’ing in the original package. I always wonder if the plastic is safe to SV in the way that Food Saver bags are. 

Regardless, my recommendation going forward is to start with a whole piece of fish and portion and vac seal yourself. The fish tastes fresher and you save some money on the packaging costs. 

Langner91

I would sous vide in that packaging.  They probably don't package food in unsafe bags.  I have sous vided (is that a word) in the original packaging.  

nolaegghead

Generally speaking, if the bags are made from polyethylene, which most are, it is food safe at sous vide temperatures.  If the bags are made from polyvinyl chloride, they are not. 

If you aren't sure, light a corner of the bag.  If it is PVC, it will smell like chlorine, very acrid, lots of soot/smoke.  Polyethylene burns fairly clean like wax with a blue flame/yellow tip.  

Actually, this might help:

https://www.boedeker.com/Technical-Resources/Technical-Library/Plastic-Identification

Ziploc bags, for example, are polyethylene and are safe for sous vide.  The vast majority of freezer bags are polyethylene and I would be surprised if they used pvc.  However, pvc is actually still safe for the heat levels you would use with fish.  It is rated safe for hot water delivery, the main problem is burst pressure drops with PVC pipes and heat.  Assuming you SV fish under 140F.

NDG

Tnx - yes good idea moving fwd.  Short term (to be safe) I guess I have to remove packaging & vac seal again ??

NDG

nolaegghead said:

Generally speaking, if the bags are made from polyethylene, which most are, it is food safe at sous vide temperatures.  If the bags are made from polyvinyl chloride, they are not. 

If you aren't sure, light a corner of the bag.  If it is PVC, it will smell like chlorine, very acrid, lots of soot/smoke.  Polyethylene burns fairly clean like wax with a blue flame/yellow tip.  

Actually, this might help:

https://www.boedeker.com/Technical-Resources/Technical-Library/Plastic-Identification

Ziploc bags, for example, are polyethylene and are safe for sous vide.  The vast majority of freezer bags are polyethylene and I would be surprised if they used pvc.  However, pvc is actually still safe for the heat levels you would use with fish.  It is rated safe for hot water delivery, the main problem is burst pressure drops with PVC pipes and heat.  Assuming you SV fish under 140F.

Great stuff . . guess I am going to ignite some plastic here at lunch . . 

nolaegghead

As a bonus, you can probably find some sweet plastics to burn for gender reveal parties.