Food Safety ?

I would like your thoughts on the following scenerio:

A bone in Pork roast is smoke/roasted to an internal temp of 195f and then chunked/pulled into small/bite size pieces and cooled to 40f in an appropriate time frame. After 4 days in this 40f cooler, it is vac-packed and frozen.

Do you have any concern with the 4 days between cooking and vac-packing from a food safety point of view?

Look forward to your thoughts.

If:

a) the pork was hot when it was pulled (>130F)

b) the pulled/chunked pork was chilled in such a way to ensure even and relatively quick cooling, i.e., not packed thickly in bags or containers which can substantially delay cooling of the interior

c) chilled to <41F

d) maintained at <41F for the entire period in question

then, no, I do not have concerns from a safety perspective.

I would have a one from a quality perspective. There is a possibility of spoilage bacteria. These bacteria are not a concern safety-wise but do grow from 29-40F, albeit slowly. I'd shoot to consume the frozen product in a relatively reasonable period of time, say 4-6 weeks tops, so as to minimize the chances of off-flavor development.

Using K Kruger's assumptions, it is probably safe to eat...but personally, I wouldn't save it after four days.

Pork's cheap, food poising can ruin an entire weekend you can be Q'ing

And you're certainly free to do--or not do--what you wish.

Not speaking to you personally, but I see this sort of response on this and other food boards frequently. It seems to me like it's decision-based-on-whim or -emotion or -fear.

Not long ago, elsewhere, I posted a response to a somewhat similar food safety questiion. The dozen posts before mine--all in agreement with each other--all advised the OP to toss out his meat. But there was no reason for him to do so, which I stated, and I gave the reasons why. The many posts after mine, excoriating my position, were telling. No one challenged what I wrote--they challenged that I wrote it.

Absent any knowledge of the subject at hand, making a decision based on fear, whim or fable is understandable, and it is certainly understandable to adopt a cautious posture in the face of ignorance. What I fail to understand is the seemingly mass attraction to jumping on the fear bandwagon rather than seeking knowledge so that one may arrive at a valid answer. I just don't get that.

Again, not speaking to you personally, RD, but tossing this question out rhetorically (or not, if anyone wishes to answer it): Using my assumptions above, where precisely would the food safety problem arise?

Thanks for the reply Kevin.

In this same scenerio, would it be true to say that even if there was a temp issue, that reheating to 165 would make the pork safe to consume???

Kevin,

I'll bite - but just because I'm curious about a few things...not challenging you. What about what happened between taking the meat off the cooker and your item A? Also, thawing and/or reheating?


During the "resting" period no part of the meat was below 130F? Cross contamination could be a concern throughout the process? Reheating methodology?

I used the 130F because you did. I thought 140F was the general rule. I'll certainly defer to you on the matter, but I am interested in the 130F vs. 140F.

I can't disagree with anything Kruger says. And I agree. There is no good logical reason to think it is not safe. I worked as a professional cook for over a decade and always took the extra cautious route. One bad meal is all it takes.
It drives my wife crazy because I won't eat leftovers that are in the fridge for more than two days.
No scientific reason, just a personal preference.

RD-- I am a very opinionated person--especially when it comes to food-, safety-, or cooking-related issues--but I am all about personal preferences. (And wherever would we be without our idiosyncracies? )

Steven-- Short answer: No, it would not be true.

Fleshed out a bit: When it comes to food safety--be it cook temps, internal temps, hot- or cold-holding, 'danger zone' issues, etc.--it is nearly always a 'time @ temp' consideration and not a temp--nor a time--thing alone. In other words, the two interrelate or correlate.

Were the criteria (a-d) met I would not have a concern, as noted. But if one or more were unknown or vague I would. Were, say, the pork pulled hot but then packed thickly in bags and put in the fridge I definitely would. Were the pork to have rested too long in the cooler and not be hot when it was pulled I definitely would.

Though pasteurization (the reduction of pathogenic and toxigenic bacteria to safe levels through heating/cooking) would have occurredwhen the butt was cooked, temp abuse (two examples of which I just mentioned above) would give me pause. This is because pasteurization is not sterilization (i.e., some bacteria might survive cooking--it must be assumed they have). Though pasteurization allows food to be consumed safely, consumption needs to take place within a specific period of time. This time period is virtually limitless provided the food remains hot (>130F throughout) but becomes limited if the temps fall below that figure. Then the clock starts.

The issue here is that those bacteria that survive cooking--and those bacteria that might have contaminated the food post cook (from handling, a cough or sneeze, placement of the food item on a not-quite-clean-enough surface) can and will grow when the temps fall into the range best suited for each bacteria's growth. Still, it's a time issue, a time @ temp issue.

We all know we can cook something--grill a steak, roast a pork tenderloin, heat a bowl of chili--and allow it to rest or cool somewhat before consumption. This isn't a problem because not enough time passes to pose one. But if enough time does pass the potential for a problem markedly increases. This is why I so often stress the need to cool relatively quickly--and thoroughly--on this board and elsewhere; both because this is an issue some people are not aware of and because so many of us so often cook food meant to be reheated at a future time.

This post is my attempt to explain time @ temp issues. Most of it concerns pasteurization but the bottom paragraphs touch on time @ temp as it relates to the danger zone. I need to do a bit of editing to the post, and I think I need to expand those bottom paragraphs into a larger, more thorough post that will make the issues of the DZ, time @ temp, cold- and hot-holding, et al., clearer. It isn't rocket science but it is science. Much of it, probably, when I can do this, needs to be read a few times so that it is better understood and thus more easily integrated and grasped conceptually so that readers can make good use of the information.

It is fine, I suppose, to take a very simple (simplistic, really) view--much like one sees on the consumer areas of the food sections of the FDA, USDA and other food-oriented websites. But some of this info doesn't make sense (because it really doesn't make sense), some is contradictory, some seemingly suggests tossing food out for the tiniest 'infraction', some elides key details. Not everyone is all that interested in the subject but we'd have less food-related illnesses if more people were (and less unnecessary waste!); and many people, imo, should be more interested--especially the non-professional but avid cooks that may cook often for many people or seek to get into catering by starting a biz from their homes. Sometimes a simple view might be just fine; sometimes one is faced with a situation like the one you stated in the OP. One can 'simply' toss the pork--but must one?

I spent several hours writing a response to above posts--as and when I could, in bits and pieces--and then, while I was typing the last few sentences of the last paragragh (in my response to Greg) I inadvertantly hit one key combination or another and deleted the whole thing. So, I'm posting this now and, Greg, I'll respond to you as soon as I can. Good questions.

Greg-- I like questions and I like being challenged. Either motivates me to learn. So, my usual brief ( ) reply:

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">What about what happened between taking the meat off the cooker and your item A? </div></BLOCKQUOTE> If the pork was >130F when pulled one can assume that it was between the time it was removed from the cooker and the time it was removed from the cooler to pull. If the butts were well wrapped in foil, and rested in a cooler with towels to help hold heat, they should remain hot for some time. But, as I point out in the post I linked to above, it's almost never the internal temp that one should be concerned with when holding intact meat cuts, such as bone-in butts, for resting. This is because the interior of the roast will remain hotter longer than the exterior surfaces. Also, bacteria do not pose a concern in regards to the interior sections of intact roasts because they do not colonize there nor can they somehow 'crawl' there. If the coolered resting phase of the butt might be prolonged then it is the surface temps that should be monitored or checked. It's the surfaces of intact cuts where bacterial growth occurs.

Should bacteria survive cooking there will be no growth unless temps fall into the DZ.

It should be noted that there are a few bacteria that are spore and toxin producers. While the vegetative bacteria (the cells that grow) are controlled through pasteurization, spores and toxins are not usually affected by 'normal' cook temps. In fact, it usually takes heat to activate spores. Still, it takes cooling to the danger zone, and time, for spores to germinate and outgrowth to occur or for toxins to be produced.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Also, thawing ... </div></BLOCKQUOTE> Thawing scenario #1: A butt, say, or a brisket, or a package of thick rib-eyes is purchased frozen from the market or purchased fresh then immediately frozen.

If there's time, the easiest way to thaw any of these items is to stick it in the fridge.

Another, quicker way, is to immerse the item in a sink or pot of cold water, changing the water periodically as it warms, replacing it with cold. This is a faster way than the fridge. The water, though cold, is warmer than the frozen item. The item thaws relatively gently and evenly.


Another way is the microwave's 'defrost'. Microwaves can easily ruin foods during 'defrosting' because they don't really defrost. They cook the food, albeit more slowly, by pulsing the microwaves for a bit then shutting off. They don't work well for thick items nor for delicate items nor items not destined to be cooked through completely, e.g., steaks one plans to cook med-rare. For some items, in a pinch, one can use the microwave to get thawing started but then finish in the fridge, in water, or on the counter, depending on the item and howsoon it will be cooked. This avoids the microwave overcooking the interior before the exterior has a chance to thaw.

Lastly, one can thaw on the counter. Yes, this is discouraged by numerous 'authorities' and disallowed by the Food Code but there is no science-based reasoning to support this. One assumes that the reasoning is that it is much easier to say 'never' than to explain why it is possible in many circumstances but, perhaps, not in others.

Thawing scenario #2: A vac-pack of pulled pork, say, or a brisket flat, or the thick rib-eyes, all cooked, all cooled relatively quickly, all frozen.

With these items it is best to either thaw in the fridge or to reheat without thawing, if possible. In the case of the pork that's been vac-packed, the bag can go directly from the freezer into simmering water; no need to thaw. Were the pork frozen in Zip-locs or, maybe, simply wrapped in plastic, then, of course, the meat would need to be thawed before reheating.

Both the brisket and the rib-eyes should be thawed first in the fridge. Reheating in a water bath is risky--for quality reasons. It is very hard to gauge the level and thoroughness of reheating in a water bath and thus, for items that can't tolerate further cooking without becoming overcooked, it is not the best option.

Though it is possible to thaw any of these items in a sink of cold water I don't recommend it if it can be avoided. This is because of possible post-cook contamination, especially by the enterotoxin producer Staphylococcus aureus. (Cross-contamination by other bacteria is possible if one isn't careful: using utensils that aren't as clean as they should be, e.g., placing the cooked item on a cutting board that was previously used for something else and not cleaned afterwards, etc.) S. aureus is rarely a problem in raw foods. Contamination of food usually occurs post cooking when food is handled, or through a cough or sneeze.

If the food is contaminated and consumed immediately--or within a reasonable period of time--toxicosis does not occur. If the food is contaminated but cooled quickly, fridged or frozen, then reheated in a reasonable period of time and then eaten in a resonable period of time, toxicosis does not occur.

It takes time for this bacteria to grow--and it takes temp abuse, i.e., temps dropping into the DZ, especially temps in the mid-90s (where it grows much more quickly--these temps, you'll note, are typical of many a hot summer day), though it can grown at a much wider temp range. S. aureus produces a heat-stable toxin. Should enough time pass for large growth to occur (10^5-10^6/gram) the food is likely toxic. Though reheating can kill the vegetative cells, it will have little affect on the toxins. This is why I stress proper and rapid cooling of foods to be reheated later; and why I stress hot-holding after cooking or after re-heating.

If needing to thaw cooked food and there isn't time for total fridge-thawing but there is some time, start thawing by immersing the item in cold water, changing the water as it warms, then finish thawing in the fridge. If there is less time, thaw in cold water, changing it a bit more frequently. But if you were the one who cooked the food, and you know the food was properly and quickly cooled, there is little to worry about if thawing entirely in a water bath. Just reheat promptly after thawing or refridgerate till reheat time.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">...and/or reheating? </div></BLOCKQUOTE> I think I covered much above. I'll add that reheat time shouldn't be prolonged unnecessarily. For reheating a whole cooked butt or brisket (or either, in, say, large chunks), slow reheating is not necessary. Though one doesn't want to cook the item any more (especially brisket), one can get its temp up fairly quickly then either serve or reduce the oven temp so that the food stays hot without continued cooking.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">During the "resting" period no part of the meat was below 130F? </div></BLOCKQUOTE> Yes. Since we're talking about butt here--butt that has been cooked to its usual temp--resting is the obvious next step--and often for several hours. 130 is the top of the DZ but if one wants to use 140 or any other number higher than 130 that's fine. I suggest temping the part of the butt (or whatever one has cooked) at a spot where it is most likely to cool sooner. This is usually the surface. Also, because bacterial growth, if any, is most likey to occur on the surfaces of intact meat cuts, all the more reason to monitor there.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Cross contamination could be a concern throughout the process? </div></BLOCKQUOTE>Yes. But it is most likely to occur after the fooditem in question partially cools and is then handled in some way. Very hot food is not likely to become contaminated by bacteria if it is still very hot. When the food cools some though, cooks are more likely to handle it--whether it is pulling the pork, slicing the brisket, transferring the steaks from the sheetpan they rested on to the cutting board, taking the grilled shrimp off the skewers, etc. This might not be an issue for foods that are going to be served promptly--but it might, especially in cases where food is cross-contaminated by unwashed hands (the fecal-oral route is an obvious vector). The problem is amplified if the food is cross-contaminated post cooling and then the food is aloowed to cool further--but slowly, as happens when food is served, left on the table after serving, packed in large thick quantities, etc. In these cases the food can drop into the DZ and remain there for some time. If the food was cross-contaminated, now, because of the lack of rapid cooling, the pathogens involved have the right temps--and, often, the time--to grow.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I thought 140F was the general rule. </div></BLOCKQUOTE>It isn't. It's the number that been around for a long time and that consumer-oriented publications, groups, websites, etc., still use. And it is, of course, the number one sees bandied about food forums and food blogs. A few points: The top end of the DZ is actually just over 127. This is the maximum point where Clostridium perfringens is a problem and it's used because its max point is higher than the maximums for the other pathogens one associates with food-borne illness. 130 adds a couple of degrees leeway.

This has all been known for some time. It is hard to say precisely why 140 is still iterated as the top end, except that the FDA/USDA/food-oriented consumer groups, etc., seem to assume people are fairly clueless when it comes to food safety. Many might be, but rather than offering and pushing reliable information--tangible, viable information--the importance of the DZ, the importance of using reliable, appropriate thermometers (they mention therms frequently but have you ever seen any stress the need for tip-sensitve thermometers to be used on thin food items?--stress that bimetal analog therms should not be used to test thin items like burgers and chicken breasts? I haven't either)--they leave it alone presumably because, since 140 is higher than 130, no harm done. I can't argue with that. But if they want to leave it at 140 'to be on the safe side', why the lack of other pertinent safe info?--the therm issue, the need for rapid cooling, the need to toss food that's been served and not temp-controlled and sitting around for long period, proper handwashing, etc. Some of this info can be found on their sites but it hardly in the forefront. It is not spread around the Net by forum posters and bloggers because it is either not there or not stressed. People have overcooked pork for years because it took the authorities ages to admit that not only was trichina in pork not much of a problem but it's killed at 137 anyway. Fine to suggest things 'to be on the safe side'--but why not be truthful at the same time? Such as: '130 is the top end of the danger zone but 130 is the minimum temperature on or in any part of the food item--so to be on the safe side we suggest 140'--and then go on to stress the therm issues.

Lastly, politics. FSIS was using 130 in the '70s and attempts were made to revise the status quo to this scientifically-based number, then and into the '80s. In committee, many States opposed changing to 130 from 140. A compromise of 135 was reached. The Food Code reflects this--135 is used as the top of the DZ in the Food Code.

If any of this needs clarity or has prompted other questions please feel free to comment or ask.

I'll stick this here because it seems like an appropriate place.

I recently posted in Just Conversation about a recall being currently conducted due to the possibility of C. botulinum in canned chili, chili sauce and corned beef hash. There has been some recent discussion on one of the food safety listservs that I am a member of. One member has pointed out that it is a well known fact that C. bot. does not tolerate a pH of less than 4.6 and questioned how and why this detail was (possibly) missed by a commercial manufacturer.

A tangential discussion was started about food safety experts in the UK calling for tighter controls on ready-to-eat salads there after testing revealed that many contain bacteria that can cause food poisoning, particularly salads containing meat or seafood. Listeria, E. coli and Salmonella were found (Listeria in 1-in-10 packages, the other two bacteria in lesser amounts.)

Pete Snyder, a food safety researcher from the
Hospitality Institute of Technology and Management in St. Paul, Minn., had the following response. It echoes my issue with washing poultry before cooking--and hits a few nails on the head, pointedly, as Pete is often wont to do.

"It is time for the government to be honest with people, if one eats food
from the dirt/ground and the only intervention is washing the food,
there is a risk of getting ill. It is very low, but not zero and never
will be. If the person lives on a farm or in the country or eats lots of
raw fruits and vegetables so they eat dirt regularly and have a
tolerance for the pathogens in dirt, they don't get sick. If they eat a
lot of prepared, cooked/pasteurized food it is up to them to pick their
fresh food carefully. A study I did here in Minnesota showed that
virtually never was there a foodborne illness in the rural, farm
counties of Minnesota. People who do not eat a little dirt regularly,
should not rely on anyone to make their fresh fruits and vegetables safe
for them. They should buy from the grocery store and take full
responsibility for making the fresh fruits and vegetables they eat safe.
It is simple, blanch/ wok the raw fruits and vegetables. Chinese cooking
does a nice job of making raw fruits and vegetables safe. Washing
won't. People also have to stop washing raw chicken in their sink at
home. Informal surveys I have done indicate that 50 percent or more want
to wash their chicken, (in the same sink they will wash their salad)
before they cook it. No wonder Campylobacter is the leading cause of
illness. Raw chicken is by far the most dangerous food in the kitchen
because of Campylobacter."

Though I'd have to check this out, I believe Campylobacter is the leading bacterial cause of food-borne illness here, Norovirus (or, Noro-like virus) the (currently) leading cause of all FBIs. (It's what has been implicated in many of the recent FBI outbreaks on cruise ships.)