Re-freezing

[RedSidedSPR]

Is refreezing bad? Why?

[katach]

I think there is a concern with bacteria growth. Also the quality of the item you re freeze will be less from the cellular break down.

[RedSidedSPR]

Gotcha. So is it ok to do it once or twice?

I want to let the tilapia thaw, than cut it all up, and put it back. I hate cutting prices off each feeding.

[chris-uk]

The issue is with the microbiology - the temps you usually defrost at are ideal for bacterial growth. If you defrost slowly in a fridge, that's the best option for the first defrost, rather than defrosting at room temp.
I'm assuming that once you've chopped up and re-frozen the pieces you will defrost the individual meals quickly and feed straight away, in that case there isn't much time for bacteria to grow the second time.

I chopped up fresh fish before freezing it earlier this week, so I have a load of individual clingfilm wraps of fish. I can defrost these small pieces in 5 mins in a bowl of warm tap water.

I don't believe there's any risk to the way I'm freezing and defrosting the fish, so as long as you're careful about defrosting your tilapia the first time you should be OK. I wouldn't advise more than one defrost/refreeze cycle.

[ConcinusMan]

I don't get the logic in that. I thaw in hot water and the food is completely thawed in a minute or two. There's no time for bacteria growth. If the snakes don't eat all of it, I refreeze immediately. Never had any issues doing that. Besides, garters can and do eat carrion in the wild. Rotten, stinking nasty dead stuff. It doesn't hurt them any more than it hurts a crow to eat roadkill off the pavement.

[chris-uk]

I don't get the logic in that. I thaw in hot water and the food is completely thawed in a minute or two. There's no time for bacteria growth. If the snakes don't eat all of it, I refreeze immediately. Never had any issues doing that. Besides, garters can and do eat carrion in the wild. Rotten, stinking nasty dead stuff. It doesn't hurt them any more than it hurts a crow to eat roadkill off the pavement.

It's about defrosting and refreezing quickly. If you left the fish to defrost for a couple of hours there is time for bacterial growth. Like you said you defrost in a minute or two and refreeze straight away. I was cautioning against a slow defrost.

Interesting point about carrion. Maybe garters aren't susceptible to food poisoning bacteria.

[RedSidedSPR]

Hmm.. Ive done it like Richard, with water, but I've never refrozen anything. I just run water on it, and feed it.

[mb90078]

If the main concern is bacterial growth, would the re-freezing take care of most of the bacteria?

[chris-uk]

A lot of food poisoning bacteria will not be killed by low temps, so although they won't continue multiplying while in the freezer as soon as the temperature rises (i.e. room temp defrosting) they get right back to multiplying and possibly causing problems.

[ConcinusMan]

If the main concern is bacterial growth, would the re-freezing take care of most of the bacteria?

No. It wouldn't. And besides, (the following really only applies to food which has already spoiled) you could heat a rotten steak enough to kill all the bacteria but it will still make you sick. This is because it is not the bacteria that makes you ill, it's the toxins they produce, which would still be present in the food even if all the bacteria was killed.

A dog or other animal could eat that steak with no harm or illness. This is because the lining of their digestive system protects them. Snakes, turtles, etc. do not get sick from salmonella(for example) because of that. We lack that protective lining and so the toxins severely irritate and cause us to vomit, diarrhea, etc.

I've tried thawing fish in the refrigerator. It always spoils before it's even thawed. Only takes one or two days for it to spoil. I just put it in a bag, submerge in hot water. It's thawed in a couple of minutes. Whatever isn't used within a few minutes can be refrozen once.