12 replies to this topic

[a_andhika]

Dear Forum,

Does anyone has literature that mention the procedure to conduct proper meat thawing? Can it be done at room temperature? At which temperature and time meat thawing can goes smoothly? Thank you.


Regards,


Arya

[hygienic]

Dear andherka:
The rough energetics of thawing a meat:
there is 4 steps for thawing meat have to be done.
1-meat frozen
core temperature of meat -5 =cavity ice crystals

2-meat temperature rises to between -1 and +1
Ice crystals begin to melt.
energy is used to melt ice.

3-meat temperature continues t rise :
water in the meat flesh melts,exept where it is in contact with crystalline ice
lining bone surfaces.or internal cavity.
flesh temperature begins to rise.variable with fal levels.

4-meat achieves +5 throughout .
no ice crystals present.


note:thawing process must be in the refrigrator this is the proper method.

other method is under potable water (tab) if u want to direct use.or direct to cooking and the water must be free of pathogenes

[Cathy]

Meat can be thawed in a cooler, under flowing water (not to exceed 70F), or in a microwave. I have not seen it recommended, nor shown as acceptable, to thaw at room temperature except in restaurant or food service operations where portions are slakced out somewhat just prior to cooking.

[Jean]

Hi Arya,

In food service establishments the recommended methods for thawing are as in a thawing cabinet or chiller which operates at 5oC and below ( to be cooked in 24 hours) or in cold running potable water with temp less than 20oC ( to be cooked immediately) after complete thawing and last in Microwave oven as per manufacturer's instruction (to be cooked immediately after thawing). Thawing at room temperature is not recommended as Cathy mentioned.

Hope this helps.

[a_andhika]

Dear Forum,

Thank you very much for the feedback. Yes, I thought so. In future we'll change the thawing procedures. How so ever, we are in the middle of battlefield to get ISO 22k cert. right now. I've validate that our thawing procedures would not procreated microbial growth, nor the decreasing of meat texture. Do you think it's acceptable?

Regards,

Arya

[Charles.C]

Dear Arya,

A topic with a much discussed history.

A Codex comment -

If frozen raw materials are used and a thawing process is included, the thawing method should be clearly defined and the thawing schedule (time and temperature parameters) should be carefully monitored. Selection of the thawing method should take into account the thickness and uniformity of size of the products in particular. Thawing should be done in such a manner that the growth of microorganisms is controlled. Thawing time and temperature parameters may be a CCP and/or an essential quality provision

Helpful but not very specific, as usual.
http://www.codexalim...85/CXP_008e.pdf.


Here is one quite detailed practical / official method presumably suitable for validatory use, (assuming it matches yr process [??]). Specific validation details in the thawing section (Ch.9) are not given however section 4.2.15 does offers an amazingly simple (the practical part anyway) microbiological procedure for the reverse process for meat. No idea how much (if any) of this logic is available / transferable to the thawing step but the concept should be IMO (need to know the basis for their APC criterion).

 thawing_____nzfa___chapter_9.pdf   782.86KB   331 downloads

An equally direct but differently targetted microbiological based validation for thawing meat is carried out here to investigate the safety aspect of processing when occurring under other than optimum conditions. The results were rather surprising IMO though apparently "official" (the interesting question is how they justified their numerical limit for "no significant growth"). I guess the concept of this methodology supports yr current thinking (depending on how you chose yr microbiology criteria [??])

http://meathaccp.wis...zen_chicken.htm.

An older but also quite nice technical document containing literature and practical validation material (eg see pgs 12,13,17 ) designed primarily for, presumably equally demanding, animal consumers (but often quoting human food standards) is here -

 frozen_thawed_meat_for_animals.pdf   314.63KB   217 downloads


Rgds / Charles.C

PS Is iso22k looking much more of a "battlefield" than BRC in yr current experience ?

[a_andhika]

Dear Charles C.,

Thank you vey much for your intense and detail answers (as always). I guess the most relevant section with my condition is the validation report from the University of Wisconsin. The Codex gives a different approach from the NZFSA (especially at freeze temperature), and unfortunately doesnt give a clear and strict thawing parameters . But I think becuse the literature was much more concerning about the Cold Chain. USDA also a good reference, but it seems not matched with my thawing procedures.

However, I am still have to figure out what will happen if the meat portions is bigger (like 2 kg), the room temperature was the same, but with longer thawing time (like 14-18 h).

Actually, the meat's temperature after thawed with my condition is still around 3-4oC. Therefore, I think it still safe, as long as it immediately processed. Maybe I will ask further information from Wisconsin. Or does anyone has another opinion?

Regards,


Arya

PS: Eventhough I dont know much about BRC (and so as ISO 22k), but IMO the BRC just like WWII. It harsh, tough, but however has a quite clear ending. As for the ISO 22k, it just like Vietnam or Gulf War, the objective of the war is doubtful, and doenst has a clear ending. Sorry if I am getting out of the topic

Edited by a_andhika, 07 September 2008 - 10:10 AM.

[GMO]

I think there is a lot of cautiousness here. For cooked meat which will be eaten without further processing, your controls need to be good to prevent the temperature increasing; however, in our current JIT universe, to thaw at 5 degrees C or lower seems daft. You can get defrosting machines (or even lorries you tag onto your building) which work at higher temperatures but are 'triggered' by core and surface probes. AFOS is one type (although I've had mixed results).

http://www.afosgroup.com/aboutUs.asp

Another way is to thaw at room temperature taking core (probe) and surface (IR) temperatures every hour. Once one exceeds 3 degrees; stick the product in the chiller. It's best to validate the process though using dataloggers to find out if you have any temperature hot spots so you know where to check.

For raw meat to be cooked, you have much more margin. Consider; what is the risk? Growth of pathogens is a concern and one you want to control; however, if you are cooking thoroughly afterwards, I would question how significant that hazard is. I'd also be easily prepared to go up to 8 degrees before chilling. I would say the only significant hazard is a quality one not a safety one. I know this would not be seen as best practice now but most dark meats and game in the UK used to be hung for up to a month and were routinely stored in butchers on meat hooks for sale. We can get a bit obsessive about chilling everything to below 5 degrees but it's all about risk assessment, evidence and HACCP at heart.

[a_andhika]

Dear GMO,

Thank you very much for your feedback. After further thoughts, I think I much aware about the quality issue rather than the food safety issue. We still have the cooking and maillard process that may reach temperature around 100 - 120oC at 30 - 90 minutes (depend on the products). Afterall, the surface temperature of the meat at mincing process (took after the thawing) is still around 3-4oC.

I've validate the texture of the meat after thawed by our method, and the result is not giving a significant decrease, or even makes the meat is deteriorate (one of the sign of high microbial content). So I'm still think our thawing method still not a hazardous practise. However, I am still looking for another opinion. Because I am still in a doubt to justificate that our method is right.

Regards,


Arya

[engan20]

Hi,

I also agreed that when comes to thawing, need to consider carefully the method and temperature. I suggest that thawing the meat in a chiller (4oC ) for 24 hours before you proceed, this kind of slow thawing allows meat to be fully defrost, inccurred only minor quality loss.


Regards,

engan

[Abdul Qudoos]

Dear Forum,

Does anyone has literature that mention the procedure to conduct proper meat thawing? Can it be done at room temperature? At which temperature and time meat thawing can goes smoothly? Thank you.


Regards,


Arya

According to me:
Thaw completely in a cool room and remove the giblets, refrigerators should be used if you know the temperature of the refrigerator and the time taken to thaw. 4 - 15 deg. celsius and time limit, Thaw in a container to catch the liquid safely, or under running tap water (no hot) once thawed keep in the refrigerator and cook within 24 hours.
Thank you for reading my post.

[SaniS]

Hi there,

what are the possible risks if I thaw meat at room temperature?

Dear andherka:
The rough energetics of thawing a meat:
there is 4 steps for thawing meat have to be done.
1-meat frozen
core temperature of meat -5 =cavity ice crystals

2-meat temperature rises to between -1 and +1
Ice crystals begin to melt.
energy is used to melt ice.

3-meat temperature continues t rise :
water in the meat flesh melts,exept where it is in contact with crystalline ice
lining bone surfaces.or internal cavity.
flesh temperature begins to rise.variable with fal levels.

4-meat achieves +5 throughout .
no ice crystals present.


note:thawing process must be in the refrigrator this is the proper method.

other method is under potable water (tab) if u want to direct use.or direct to cooking and the water must be free of pathogenes

[GMO]

Hi there,

what are the possible risks if I thaw meat at room temperature?

If it's raw meat, then your pathogen loading could increase a lot and there is a small risk that it might not be reduced enough by your cooking process that you could still end up with an infective dose; however, if you're sensible about it and move it to a chiller for the final bit of defrosting as soon as the core or surface temperature exceeds 0 degrees you should be fine.