[sci.bio] Summary of replies re: repeatedly thawing and refreezing meat

jdchrist@watcgl.waterloo.edu (Dan Christensen) (07/13/89)

In article <10539@watcgl.waterloo.edu> I wrote:
>I have heard that once frozen meat has been thawed, it is not wise
>to refreeze it.  Is this true?  If so, what can happen?  Why?
>Does this apply to any other foods?

I received four replies.  Two didn't suggest that bacteria would
form, but thought that it was a bad idea for other reasons:

# From: Eric E. Snyder <eesnyder@boulder.Colorado.EDU>
# 
# I would suspect that repeated freeze-thaw cycles would start lysing 
# the cells, turning your fine steak into beef homogenate (yuck!).  Also,
# it is general practice to avoid dealing out such treatment to _any_
# protein since it eventually leads to loss of activity (enzymes) or
# some other form of decomposition.  

% From: munnari!licr.dn.mu.oz.au!morton@uunet.UU.NET (Craig Morton)
% 
% 	to the best of my knowledge the main problem with thawing/
% refreezing is that it allows any bacteria etc. in the meat to commence 
% growth.  If repeated too often this will lead to a high level of bugs, with 
% few of the normal signs such as odour etc.
% 	Thus if the meat is cooked after thawing, killing any bacteria it 
% carries, thawing/refreezing is no longer a problem (unless you roll it in 
% the dirt at some stage!)

Two suggested that bacteria would form more readily:

& From: munnari!hitech.oz.au!clyde@uunet.UU.NET (Clyde Smith-Stubbs)
& 
& I understand it to be that there is an increased risk of bacteria
& growing during the thawing phase. Repeated thawing and re-freezing
& increases the risk.

* From: citi!bellcore!nvuxl!myron@mailrus
* 
* Did you hear this is bad in terms of health or in terms
* of ruining the taste.
* I would be surprised it is unhealthy, but the meat
* certainly would never taste the same.  Freezing and
* unfreezing causes contraction and expansion of cellular
* water molecules, breaking up tissues.

Thanks for the replies!

----
Dan Christensen, Computer Graphics Lab,	         jdchrist@watcgl.uwaterloo.ca
University of Waterloo, Waterloo, Ont.	         jdchrist@watcgl.waterloo.edu