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Author Topic: What goes wrong with frozen food if you thaw and refreeze  (Read 1102 times)

Offline syhprum

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We are told its very bad for you, I hesitate to experiment!


 

Offline evan_au

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Re: What goes wrong with frozen food if you thaw and refreeze
« Reply #1 on: 21/03/2016 08:43:06 »
The repeated expansion of ice crystals as food freezes and thaws repeatedly will break more cell walls, gradually turning the food into mush.

Every time the temperature rises above 5C, any bacteria in the packaged food will also defrost and resume growing. The mush will be much more digestable than food with the cell walls intact, so the bacteria can grow more quickly.

There is probably a difference between the risks for:
  • frozen food which is still sealed in its original frozen food packaging, and has cycled between freezer (-18C) and fridge (4C)
  • vs frozen food which has been opened, exposed to kitchen bacteria, left at a warm, bacteria-friendly 25-35C for a few hours and then frozen and thawed repeatedly.
  • Presumably the latter would be more of a risk?
But the guideline of not reheating cooked food more than once is probably a wise precaution. Minimize the amount of time the food spends between 5C and 60C.
See: http://www.foodstandards.gov.au/consumer/safety/faqsafety/documents/Cool%20_and_reheat_food.pdf
 

Offline wolfekeeper

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Re: What goes wrong with frozen food if you thaw and refreeze
« Reply #2 on: 21/03/2016 22:12:29 »
We are told its very bad for you, I hesitate to experiment!
Nothing - it depends how you defrost it.

If you defrost it at room temperature, then you can only defrost it once, because it reached room temperature, and the bacteria are multiplying like crazy; you have to cook it immediately, or throw it away.

But if you purchased fresh food that could last a week in the fridge, and you froze it as soon as you got it home, and then defrosted it in the coldest part of the fridge, left it there for a day or two, you can refreeze it again without problems.

The only subtle catch is that it takes time for the food to reach freezer temperatures after you put it in the freezer, and the bacteria are still growing, albeit slowly, until it gets hard frozen again, so (say) getting it out of the freezer and putting it into the fridge, and then back into the freezer again every day for a couple of weeks would be pushing your luck, even if it was in the freezer for half the time.
« Last Edit: 21/03/2016 22:27:03 by wolfekeeper »
 

Offline alimeeabey

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Re: What goes wrong with frozen food if you thaw and refreeze
« Reply #3 on: 21/04/2016 09:41:04 »
Itís not good to freeze, thaw, and refreeze a food item. When you thaw for the second time, it will break down even more cells, leaching out moisture and deliciousness and changing the integrity of the product.
 

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Re: What goes wrong with frozen food if you thaw and refreeze
« Reply #3 on: 21/04/2016 09:41:04 »

 

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