Refreezing thawed foods

"Refreezing -
Once food is thawed in the refrigerator, it is safe to refreeze it without cooking" - USDA fact sheet (freezing and food safety section)

I did a trial and thawed a frozen raw food in potable running water, processed it and stored it in the freezer, operating at a temp of -18oC, for 2months. Surprisingly, it passed the microbiological analysis.
My question is, can I use this practice in the kitchen?

Note: The product is beef burger

Regards,
Food safety boy

Personally I wouldn't.


Firstly I would never thaw meat in water as not only does this increase the moisture in the meat and wash away some of what will be contributing to the flavour but also bringing the meat up to chill temperature will mean some bacteria (e.g. Listeria) are then able to grow. By defrosting in water as well you're then spreading potentially pathogenic bacteria around.


Freezing will kill some bacteria but it can't be relied upon for it which might be why it passed.


What I would say as well is you trial is flawed. You need to have tried more than one experiment to validate this process and also unless you know the starting material was worst case scenario, how do you know the process is safe?


Another consideration, particularly with meat is the quality. The freezing and defrosting will cause ice crystals and depending on how quickly you freeze will depend on the crystal size and, hence, the damage done to the cells and structure.

Dear foodsafetyboy,

Slightly

It doesn’t exactly relate to yr rather ambiguous post (eg what micro.analysis?) but you might be interested to know that thousands of tons of whole, slightly processed, fish is routinely frozen at sea in blocks. On land, these blocks are subsequently thawed in water and further processed into fish meat or fillet blocks which are themselves frozen again. These blocks are then sold on again to processors who cut the frozen raw blocks to produce thin slices which are then battered/breaded to yield fish fingers. The fingers are boxed and the boxes frozen again. And hence to the supermarket.

Basically, the bacterial control is done via “good” quality raw material and processing time/temperature parameters although the numbers will rise. Environmental contamination is controlled by hygiene.

Of course it is likely that beef has (much) more contamination in the starting material, eg fecal related, so the cumulative risks will then be greater as noted by GMO and practically well demonstrated by various historical and fairly current incidents / disasters.

I hope you don’t eat yr beefburgers raw or slightly cooked.

Rgds / Charles.C

Dear foodsafetyboy,

Slightly

It doesn’t exactly relate to yr rather ambiguous post (eg what micro.analysis?) but you might be interested to know that thousands of tons of whole, slightly processed, fish is routinely frozen at sea in blocks. On land, these blocks are subsequently thawed in water and further processed into fish meat or fillet blocks which are themselves frozen again. These blocks are then sold on again to processors who cut the frozen raw blocks to produce thin slices which are then battered/breaded to yield fish fingers. The fingers are boxed and the boxes frozen again. And hence to the supermarket.

Basically, the bacterial control is done via “good” quality raw material and processing time/temperature parameters although the numbers will rise. Environmental contamination is controlled by hygiene.

Of course it is likely that beef has (much) more contamination in the starting material, eg fecal related, so the cumulative risks will then be greater as noted by GMO and practically well demonstrated by various historical and fairly current incidents / disasters.

I hope you don’t eat yr beefburgers raw or slightly cooked.

Rgds / Charles.C

I think that the key factor for this example is that it is the process. The entire process is based on this practice happening.

With the original question, what is the "normal" process.

Chances are it should be "thaw what you want. Use it. Toss what you don't use".

If you are considering "Thaw it. Work out what you want and refreeze the rest. Use it." then here are the immediate issues I see:
1. how do you guarantee a fast turnaround?
2. how do you guarantee a limited number of refreezes?
3. how do you convince the sceptics?

In the eTemperature software we threw in the calculation of ice-days to predict the accumulative effects but would you be prepared to put a temperature logger with each pack that you thawed and refroze?

Cheers,
Shane

Thanks for the reply guys.

Some process would actually look like
Frozen - thawing - cooking - storage (as per USDA fact sheet)

I just did a trial for
Frozen - thawing - frozen storage

The frozen beef burger (from my trial) was sent for microbiological analysis (APC, E.coli, Staph, Salmonella) on the first month and on the 2nd month were it all passed.

My main question actually is if "refreezing thawed food safe?"
Following FDA food code 2009 approved method of thawing (ref 3-501.13)
I know that this will be more of a quality issue (as explained by GMO) since I am using slow freezing.

Thank you.

Regards,
FSB