Frozen fish, marinated then re-frozen -- okay to eventually sous vide?

September 3, 2022 6:34 PM

In trying to hack my future dinner party planning, I've discovered the joys of sous vide for marinated pork, but now want to try it on nice fish like Mahi Mahi. Only problem: I want to marinate the fish first, freeze it, and then sous vide it the day of the party. But all the fish has been previously frozen where I live in rural NM. Is this plan sanitary/wise?

What I usually do is marinate raw pork chops, vacuum-seal them, then freeze them until I have a party. Then the day of the party I throw the frozen chops in the sous-vide device until cooked and finish them on a cast iron pan -- which is both time-saving and delicious. Beef is too $$ and I've done pork to death, so I'm looking into fish now. But all the nice cuts of fish at my stores have been frozen already (and I assume the mail-order fish is also frozen. If you know of non-frozen fish-by-mail -- pls share!)

Is it safe to take this fish, (in either frozen or thawed form) and marinate it, then vacuum pack it and refreeze it for future sous vide-ing? If not, what other options should I consider? Thanks!

posted by egeanin to Food & Drink (12 answers total)

Best answer: So this is only like a partial answer to your question, but as a sous vide person I would have no problems unsealing frozen fish, marinating, sealing, repacking, refreezing if that's how you do. That doesn't set off my food safety alarms at all. I would say though that you might not even need that - good fish finished with a pan sauce might not need any kind of marinade.

The rest of my answer will go to this article for sous vide cheesecake in single serving jars for your dinner planning needs. Honestly you can skip the crust; just make as many of these as you need the day in advance or in the morning and you have FANCY DESSERT covered.
posted by true at 6:44 PM on September 3, 2022

If there is any question, why subject your guests to the doubt? I have personally broken off friendships of people who don’t cook food safely when they gave me food poisoning. Please revise the menu to something you know is safe out of respect and consideration for your friends.
posted by metatuesday at 7:00 PM on September 3, 2022

I don't know about the safety of it, but couldn't you try it for your own dinner one night in advance of the party such that if it sucks you can pivot.
posted by JohnnyGunn at 7:00 PM on September 3, 2022

Best answer: I would be concerned mostly about texture here - thawing and refreezing fish seems like it would lead to mushiness. But I have never sous-vided anything so maybe you aren’t worried about that?
posted by Lawn Beaver at 7:05 PM on September 3, 2022 [15 favorites]

Best answer: Is there a compelling reason not to buy frozen fish and leave it frozen until a day or two before your party, marinate and vacuum wrap (or buy thawed, previously frozen fish the day before)? You still don't have a lot of fuss the day-of, and don't need to worry about whether or not you're going to make your friends or family sick.
posted by kate4914 at 7:34 PM on September 3, 2022 [3 favorites]

IME you don't want to marinade fish as long as red meat, so I wouldn't want it to sit in marinade for that long anyway. But I don't see where your plan is dangerous from a good safety standpoint, I'd remove an additional day from the allowed time for the frozen cycle; i.e. if you buy it and it'd be good for four days, and you marinade and freeze, then if use it within one day of unfreezing instead of two.

But I agree the texture might be bad.
posted by flimflam at 7:40 PM on September 3, 2022 [1 favorite]

Response by poster: Definitely don't want mushiness -- that's one of my concerns here, second of course to safety. I would never do anything risky -- I'm just not sure if it even IS risky. @metatuesday - whether or not it's safe is literally my question.
posted by egeanin at 7:51 PM on September 3, 2022 [4 favorites]

Best answer: Guidance I've seen is that this is safe if the fish was thawed in the refrigerator -- not in tap water, not in the microwave. Here's one big shipper-of-frozen-fish-to-consumers talking about refreezing's safety (also quality).
posted by away for regrooving at 8:23 PM on September 3, 2022

Best answer: Safe, yes. Quality, no. Freezing, thawing, and refreezing before cooking would be a no go from me. If you want to use frozen fish, just buy it, then thaw and marinate the day of/day before cooking. Why would you need to freeze it a second time? Freezing protein more then once will just break it down and destroy the texture. Fish is so delicate and so much better when fresh. Of all the proteins that you could use, fish is the last one I would subject to a double freezing.
posted by evilbeck at 11:05 PM on September 3, 2022 [3 favorites]

Best answer: I think people may be talking about two different things. There is no reason not to take the frozen fish out of the current packaging, place it in the sealable packaging with marinade while frozen and put back in the freezer sealed.

Where it gets much more iffy is if you want to defrost it, then add the marinade and then re-freeze. May still be fine from a food safety perspective if overall age of product is fine and defrosted in the fridge but it definitely creates more variables. And it does nothing for the fish’s texture.

Or you defrost and just add the marinade to the bags before it goes into the sv device.
posted by koahiatamadl at 11:42 PM on September 3, 2022 [2 favorites]

Best answer: So, I'm pretty sure everyone is answering you based on the thought you are buying fish that is frozen at time of purchase. I think you mean you are buying "fresh fish" from a store, that to reach you was frozen in transit. Most people would freeze that fish without a thought because it's not common knowledge this is how it's transported and they think they are doing the first freeze.

I'd mostly be concerned about over-marinating using your process. Maybe freeze the marinade separately, defrost both in the fridge overnight and then combine in the sous vide bag 30 minutes before you want to cook?
posted by Adifferentbear at 5:37 AM on September 4, 2022

Response by poster: Thank you!! This is very helpful.
posted by egeanin at 7:28 PM on September 4, 2022