I will do science to it! Smoke + Sous Vide

Discussion in 'Electric Smokers' started by christhompson, Apr 7, 2010.

  1. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    This Sous-Vide is very useful but has some limitation...DO NOT INJECT ANYTHING YOU PLAN TO SOUS-VIDE...Once pre-cooked/smoked Sous-vide is great at keeping the meat at a set point temp and continueing to tenderize it. If using SV from Raw it is recommended that you keep the meat thickness to 2 1/2 inches or less. Lastly, SV must be done with CIRCULATION!!!! Throwing a chunk of Bagged Meat in a Crock Pot of 130*F water will not get you anything but Sick, if any mishandling or contamination took place...Good luck...JJ
     
  2. Dave and JJ,

    I appreciate the input, but I question it.  My understanding, based on the exhaustive discussion to be found in   http://www.douglasbaldwin.com/sous-vide.html[font=arial, helvetica, sans-serif]  (see Part I, section 1 for the non-technical summary, the appendix if you want the math) is that the widely-cited 140 degree figure is more than necessary, because it doesn't take into consideration the length of time that meat will be in the sous vide bath.  Yes, bacteria are killed more slowly at lower temperatures, but with sous vide over a 24-hour period such as I am suggesting, you will have more than plenty of time to reduce the amount of bacteria by a factor of one million, the recommended ratio.  140 will guarantee a much quicker bacteria kill, and is a good idea if you are using a "quick" method like frying or searing in a hot oven, but it is more than is necessary for sous vide.[/font]

    [font=arial, helvetica, sans-serif]Now, of course I would be interested if you have any information that contradicts Baldwin (who seems pretty solid on the science.)  But non-scientifically, I can report that I have cooked (non-smoked) tri-tips several times at 131 for 24 hours, and am still kicking.  So, I have not just contemplated my ideas; I have executed them.  I would worry a bit about trying to sous vide a big chunk of meat like a pork shoulder or prime rib, because as Baldwin indicates, the bacteria kill will depend on the thickness of the cut.  But tri-tips, at least the ones I buy, are typically less than two inches thick -- definitely not a problem by his numbers.  Also, while I don't have an immersion circulator, I don't think it stands to reason that the temperature throughout an entire tri-tip will not come to the same level over 24 hours, provided you remove all air from the sous vide bag and make sure that the bag stays completely submerged, so that you are cooking completely by conduction.  I have checked the thickest areas of my tri-tips with a Thermapen when taking them out of the bath, and have found the center to be at exactly the same temperature as the surrounding water.  I can see the need for circulation in a big, uncovered tank, but in a covered, heavy metal pot whose temperature is regulated by a PID controller I think you get essentially complete heat equalization within a couple hours.[/font]

    Please, though, if you have any data that really contradicts any of this, I would love to hear it.

    craigkl
     
  3. daveomak

    daveomak Smoking Guru OTBS Member SMF Premier Member

    Since this topic is somewhat active, I read Douglas Baldwins "brief", that was highlighted in the above post..  I am not for or against Sous-vide... I know it is popular in high end restaurants and on Iron Chef.... Looks very interesting and obviously makes some gastronomical delights....  Everyone on this forum is free to experiment making great food.... That is what we do here....   Carry on..... Dave

    http://www.douglasbaldwin.com/info.html......Information on Douglas Baldwin and his credential.. Read all the sections to become fully educated about the processes....

    Disclaimer about his book, he wrtote, at the end of the Sous-Vide section.....

    If you have any specific update requests, please email me. In my next updates I plan to: update the egg section to include my table for core temperatures between 60° and 67°C in a 75°C water bath and the results of Vega and Mercadé-Priet (2011); add a chapter on cooking fruits and vegetables; and revise the basic techniques chapter to improve readability and add some new results. I will try and make these changes in the next few months, but I do applied math research 60+ hr/wk and so have very little time available to work on this guide.

    Disclaimer: All of the information contained in this guide is intended for educational purposes only. Douglas Baldwin makes no guarantees, warranties or representations, implied or express, as to the appropriateness, timeliness, accuracy, completeness, and/or usefulness of any of the information in this guide. There may be mistakes in the information presented. Douglas Baldwin assumes no risk or obligation for your use of this guide.

    Feel free to read the info about the book and make your own descision as to whether or not you want to continue with Sous-Vide.....

    Again, I think Sous-Vide is pretty neat.... Enjoy your adventures in Gastronomical delights... And keep it safe....   Dave
     
    Last edited by a moderator: Mar 13, 2012
  4. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    Craig you suggest I read Baldwin...I have Taught Sous-Vide for several years using the information taken from Baldwin...Nothing in my statement contradicts Baldwin it Reiterates it!...Additionally I supported and agree with your use of pre-Smoking then using Sous-Vide to tenderize...I simply added the main Safety issues that need to be addressed with SV. Don't Inject...Limit Meat thickness to 2 1/2 inches or less and Circulation is the key to Proper SV cooking...I have included Baldwins words below...Do I really need to change, "Must be done with Circulation" to "highly recommend" as Baldwin uses? Additionally Baldwin discusses that Bacteria which are of primary concern but does not go into detail on Heat Stable Toxin generating Bacteria which can be a Huge thread with Injected Meat...

    Lastly my biggest problem with this statement of yours..."  But non-scientifically, I can report that I have cooked (non-smoked) tri-tips several times at 131 for 24 hours, and am still kicking. So, I have not just contemplated my ideas; I have executed them." and I have Defrosted meat on the counter for 12 hours, and never made anyone sick!...Does that mean what you and I have done without consequence is a good idea?  ...JJ

    "Most home cooks use a commercial rice cooker, a steam table or counter-top food warmer, a slow cooker or crock-pot, or a counter-top roaster. The most important consideration when purchasing such a device is that it must use a manual switch (which will not be reset when the power is turned on and off by the temperature controller). Many people prefer a rice cooker or steam table because they react faster than slow cookers and roasters (and so have less temperature over shoot). Moreover, because they are heated from below, rice cookers and steam tables often have sufficient convection currents to keep the water temperature spatially uniform; uncirculated slow cookers and roasters can have cold spots of as much as 10–20°F (5–10°C)! Regardless of the heating device, I highly recommended that a circulator be used in conjunction with the temperature controller. The most popular options for circulating the water is an aquarium air bubbler – aquarium pumps which must be submerged in the water are not designed to operate at sous vide temperatures and quickly fail. "
     
    Last edited: Mar 12, 2012
  5. sprky

    sprky Master of the Pit OTBS Member

    This is all very interesting stuff. I had never herd of Sous-Vide before. I guess in a way I have used it before with out knowing it, since I have reheated smoked meats in a vac sealed bag in a pot of water. Learn something new around here all the time. 
     
  6. I think we are converging on agreement here.  As a point of reference, let me quote Baldwin directly from http://www.douglasbaldwin.com/sous-vide.html:

    While there are many ways to kill food pathogens, cooking is the easiest. Every food pathogen has a temperature that it can’t grow above and a temperature it can’t grow below. They start to die above the temperature that they stop growing at and the higher above this temperature you go, the faster they die. Most food pathogens grow fastest a few degrees below the temperature that they start to die. Most food pathogens stop growing by 122°F (50°C), but the common food pathogen Clostridium perfringens  can grow at up to 126.1°F (52.3°C). So in sous vide cooking, you usually cook at 130°F (54.4°C) or higher. (You could cook your food at slightly lower temperatures, but it would take you a lot longer to kill the food pathogens.)

    While there are a lot of different food pathogens that can make you sick, you only need to worry about killing the toughest and most dangerous. The three food pathogens you should worry about when cooking sous vide are the Salmonella  species, Listeria monocytogenes, and the pathogenic strains of Escherichia coliListeria  is the hardest to kill but it takes fewer Salmonellaor E. coli  bacteria to make you sick. Since you don’t know how many pathogens are in your food, most experts recommend that you cook your food to reduce: Listeria  by at least a million to one; Salmonella  by ten million to one; and E. coli  by a hundred thousand to one. You can easily do this when you cook sous vide: you just keep your food in a 130°F (54.4°C) or hotter water bath until enough bacteria have been killed.

    How long does it take for you to reduce, say, Listeria  by a million to one? Your water bath temperature is very important: when cooking beef, it’ll take you four times longer at 130°F (54.4°C) as it does at 140°F (60°C). What you are cooking is also important: at 140°F (60°C), it’ll take you about 60% longer for chicken as it does for beef. Other things, like salt and fat content, also affect how long it takes; but these difference are small compared with temperature and species.

    Baldwin then goes on to provide tables, based on type of meat, thickness of meat, and temperature, which show the amount of time that's necessary to kill bacteria.  For instance, for a piece of beef or pork 30 millimeters (about 2 inches) thick, his table indicates that 3 hours at 131 would be sufficient to attain that ten-million-to-one kill ratio that is necessary for food safety.

    So assuming I agree with JJ, here's the way I'd put it: with sous vide, where you are cooking relatively thin (2 inch or less) pieces of meat by conduction from the surrounding water, you are going to have much more efficient heat transfer than you do with air in an oven (or smoker) surrounding a big, irregularly shaped piece of meat. If Baldwin is correct, three hours of sous vide at 131 should do it for a two-inch-thick tri-tip.  Of course, to achieve sous vide's signature effect of completely breaking down the collagen and tenderizing a relatively tough cut of beef like tri-tip or a chuck roast while still keeping it rare, you normally want to go much longer than that, say 24 hours, so at that point you are way  beyond the margin of error for killing dangerous bacteria. 

    But: that is very different from cooking a big, irregularly-shaped piece of meat in a smoker.  It's a lot thicker than 2 inches, and in a smoker, you are cooking by convection, not conduction.  (You can stick your hand in a hot oven for a couple seconds without burning it by convection, but you can't put your hand in the stew in that oven for a couple seconds without experiencing severe burns by conduction.) So given the inefficiency of convection cooking, applied to a large chunk of meat, 140 makes total sense.  Your meat thermometer may not be touching the very coolest spot, and you want to make sure that every bit of that roast has gotten to Baldwin's safe point and stayed there long enough to kill the bacteria.

    There is another point to be gleaned from Dave's example from Kerri Harris and JJ's comment about leaving meat sitting on the counter for twelve hours.  If your meat has an abnormally high amount of bacteria in it to begin with, of course it is going to take longer to get to a point of safety even with a ten-million-to-one kill ratio, and at some point you should probably throw the meat out.  But for meat taken straight from a 40 degree refrigerator and heated at the temperature and time Baldwin specifies, there shouldn't be a problem.  Assuming Baldwin's numbers are correct, Kerri Harris's danger range of 50 to 130 is a little too high on the high end; it should be more like 126.2, plus a little margin for error.  But I'm not going to eat a piece of meat that has been held at 95 for 12 hours in the first place, and I'm going to stick to Baldwin's 131 as a minimum for cooking beef or pork sous vide.

    ==================

    I will have more comments to offer about the circulation issue after I do my next round of sous vide.  Per Baldwin, I believe that convection currents in a covered, highly conductive pot like a All-Clad or Le Creuset dutch oven (my technique, using a hot plate) are sufficient to guarantee an even temperature throughout the whole sous vide bath, even without a circulator.  But I'm not going to claim to know  until I run some experiments.  So far, I have simply noted that the temperature of my meat as measured by my Thermapen matched the temperature registered by the PID controller when I took it out of the sous vide bath.  

    Meanwhile, back to the issue that got this all started, I am looking forward to a pink, tender, perfectly-smoked tri-tip real soon.

    craigkl
     
    Last edited: Mar 12, 2012
  7. shoneyboy

    shoneyboy Master of the Pit OTBS Member

    [​IMG]
     
  8. Not to stir the pot even more, but I have quite a bit of experience with sous-vide, both with custom-built immersion circulators, and commercial setups.  At home, I have a sous-vide supreme, and it gets quite a bit of use. 

    A chuck roast, seasoned, seared, then vacuum sealed and cooked at 135F for 72 hours absolutely transforms a humble cut of tough, but extremely flavorful meat into a perfectly medium steak, with a texture that's nothing short of amazing.  It has the texture of a thick, medium / medium rare ribeye, and all the intense flavor you expect from a chuck roast.

    [​IMG]

    72 Hour Sous-Vide Chuck Roast Over A Roast Turnip Puree With Arugula

    Short ribs are another thing that can be cooked the same way, and come out fantastic.

    At some point, I plan to smoke some brisket for a few hours, then vacuum seal it and finish it off sous-vide.  Medium-rare smoked brisket, juicier and more tender than anything a smoker could put out alone...  It'll be an interesting experiment, although I'm not sure how well the smoke will penetrate.  Only one way to find out...
     
    Last edited: Mar 22, 2012
  9. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    Sous-Vide is a great and useful tool...Done Properly...As you state you have and use the proper equipment designed for the job. It is just important that people understand, injecting should not be done and you can't simply throw a hunk of meat in a Ziplock bag then in a Crock Pot and be guaranteed a safe result...JJ
     
  10. Injecting is a sort-of bad idea.  Say you inject a piece of ribeye, and you want it to be cooked rare, you're creating a pathogen-rich environment. Say you want that same piece of injected beef cooked to medium-rare?  Once the steak is fully up to temperature, holding it at mere 130F for 112 minutes will give you a 5 log reduction in foodborne pathogens...perfectly safe to eat, no matter how many "surface baddies" you shove down into the tendrils of the meat.  I will concede, however, that you ABSOLUTELY must know the thickness of your meat, and at what point it will be fully up to temperature.  Without that information, you're setting yourself up for failure, and your lower GI up for a rough couple of days.

    Would I do it?  No, because the ends don't justify the means.  I'm not afraid that I will get sick, though.

    On the Ziploc bag + Crock Pot front, we're mostly in agreement.  You have to be able to trust your equipment if you're going to walk away for any length of time.  I trust that people can make a great sous-vide setup with a Crock Pot and a PID controller, but I'd be watching it like a hawk for the first few cooks, just as I will with my new smoker.  I'm uncertain about the safety of using Ziploc bags at relatively high temperatures, and I can't say I trust their seal, but I'd wager there isn't poly breakdown at 135F.

    Nothing is impossible.  I never rule anything out.  I'd never say, "You can't do X with equipment Y."

    I am, however, an advocate of having the right tools for the job, and a Crock Pot and a Ziploc bag are the sous-vide equivalent of using a pair of Vise Grips to remove lug nuts.  It might get you to the finish line, but it's not the route I'd recommend.
     
    Last edited: Mar 22, 2012
  11. zackly

    zackly Newbie

    That is beautiful!

    I too made a chuck pot roast (cooked M-Wed) sous vide but mine came out less rare even though I cooked it only 48 hours @ 131F. It tasted great but I like the looks of yours better.

    When I removed the beef I put in a 5# octopus for 4 hours @ 180F last night. It's sitting in my fridge in olive oil & garlic. I'm going to grill it tomorrow for the boys @ work.

    Close to 80 degrees near NYC today.

    Grillin & chillin tonight followed by a fat cigar under the stars.

    Life is good!
     
  12. On the Ziploc bag + Crock Pot front, we're mostly in agreement.  You have to be able to trust your equipment if you're going to walk away for any length of time.  I trust that people can make a great sous-vide setup with a Crock Pot and a PID controller, but I'd be watching it like a hawk for the first few cooks, just as I will with my new smoker.  I'm uncertain about the safety of using Ziploc bags at relatively high temperatures, and I can't say I trust their seal, but I'd wager there isn't poly breakdown at 135F.

    -------------------------

    My understanding is that Ziploc bags will work OK for meat in the 130-140 range, but not for vegetables where you are breaking down the pectin around 185.  Foodsaver bags are fine for this purpose, however, and you also get a better vacuum than you ever will trying to suck the air our of a Ziploc with a straw.  Hence, better heat conduction.

    Agree also on being able to trust your equipment, but I'd distinguish between a CrockPot/PID setup, and something like an All-Clad or Le Creuset dutch oven on a hot plate with a PID controller.  Pots like those are designed to transfer heat up the sides of the pot, and I believe you have a heavier-duty heating element in the hot plate.  What I am not completely sure about is the circulation, although sticking my Thermapen in different areas of the pot, I have never noticed any hot or cold zones.  Water transfers heat pretty efficiently.  Next experiment (soon) I plan to eyedrop some food coloring into the water and see how quickly convection currents disperse it.  My guess is, pretty rapidly, but this is why you run experiments.  More to follow.

    -----------------------

    I am, however, an advocate of having the right tools for the job, and a Crock Pot and a Ziploc bag are the sous-vide equivalent of using a pair of Vise Grips to remove lug nuts.  It might get you to the finish line, but it's not the route I'd recommend.

    Agree again!  Except, Vise Grips and a lug wrench each only cost a few dollars, whereas a Sous Vide Supreme costs a lot more than a PID controller and a pot you already own.  The SV Supreme also takes up a lot of room in a small kitchen.  But in a financially and spatially ideal world, absolutely it's the better choice.
     
  13. daveomak

    daveomak Smoking Guru OTBS Member SMF Premier Member

    Pee Bee

    Once the steak is fully up to temperature, holding it at mere 130F for 112 minutes will give you a 5 log reduction in food borne pathogens...perfectly safe to eat, no matter how many "surface baddies" you shove down into the tendrils of the meat.

    Pee Bee, morning.....  I'm trying to understand the above statement....  I know there are temp/time formulas for pasteurization of milk as an example.....  I had assumed, those time/temp tables were for a fairly clean, not deliberately injected with food borne pathogens, to insure a safe product....   Are you saying "one can deliberately inject food borne pathogens into a hunk of meat" and have a perfectly safe product to eat (once it reaches the proper internal temp) if held at 130*F for 112 minutes ????

    If that is true, then could I find a road kill deer and sous-vide the critter, using the above criteria, and have perfectly safe venison to eat......   I'm having trouble wrapping this brain around "food borne pathogens" being safe to eat given enough time at 130*F .....   Also, please cite the "food agency" and maybe a publication or two so I can read up on it..... 

    Not saying you are in error in you presentation, just saying I would like to verify it for my own curiosity...    Thanks, Dave... 
     
  14. Dave,

    I assure you, I'm not trying to sound snarky, just as you weren't, but pasteurization isn't really breaking new ground.  The most common foodborne pathogens cannot live at 130F.  Holding meat at that temperature kills the pathogens, so you would not be ingesting live strains.

    Here's an excerpt from a magazine that gives you some background on holding temperatures versus time for common foodborne pathogens.

    http://www.foodsafetymagazine.com/article.asp?id=1699&sub=sub1

    "Most common foodborne pathogens" assumes that your meat has been kept at the proper temperature.  Clostridium botulinum is not considered "common", and can survive at 130F, but wouldn't be a concern if the meat was properly handled and refrigerated.  Grabbing a chunk of roadkill and holding it at 130F isn't going to protect you from botulism (unless you live in the great white north, and the roadkill has been frozen the whole time).  You suffer the same risks of botulism by smoking meat as you do cooking it via immersion circulator / sous-vide.
     
    Last edited: Mar 23, 2012
  15. daveomak

    daveomak Smoking Guru OTBS Member SMF Premier Member

    PeeBee, Thank you very much for the article.... It sheds light on areas of temp / time vs pathogens that were "obscure" to say the least....  If I knew what pathogen, bacteria, parasite etc that was the "culprit" I could adjust the times and temps accordingly....   Me, being and idiot in most respects, need an all inclusive guideline to protect those I feed... (family, friends and last but not least your humble gourmand) ....  At least I can now figure out some   time / temp / pH  guidelines that will work in a given recipe ....  

    I have looked at Sous-Vide with interest in the past.... Knowing enough that food borne illness could multiply to deadly levels in time and at certain temps, have halted my pursuits in that arena....  The Web, with all its articles that are incorrect, by authors that are lacking in skills associated with the topics they write, and "heresay" articles by the Joe-Blow authors,  dealing with "life threatening" hobbies was not for me..... 

    At least at this forum, we have a very knowledgeable group of people that regularly "huddle" to consensus answer questions regarding food safety if the question is an outlier.... we regularly rely on the gov't agencies for "text book" questions....   Our aim is to provide a direction, with safety in mind, to our members and guests for wholesome food production...

    I would encourage anyone interested in Sous - Vide to gain some level of expertise in understanding food borne illness and it's destruction before "leaping into the warm water" so to speak....

    PeeBee, Thanks again for the information....   If you find any other articles that are on this topic.... please include them here for all to read......  Dave
     
  16. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    Great article. It demonstrates why people get away with doing Potentially Dangerous things like defrosting on the counter and warming 8Lb Butts to room temp before going in the smoker. But since there are no absolutes and thing do go unexpectedly wrong safe sanitation and cooking practices should still be followed. Thanks for the info...JJ
     
  17. In Modernist Cuisine, there's a chapter dedicated to this, as well.   The first paragraph of "Common Misconceptions" very succinctly describes the point I try to make when I try to discuss the subject...

    "Once upon a time, some well-meaning officials decided that food safety recommendations should include only temperatures instead of time-and temperature combinations. This decision, perhaps the worst oversimplification in all of food safety, has led to years of confusion and mountains of ruined food."

    Further along in on the page:

    "Once you eliminate time from the standards, the strong tendency is to choose a temperature so hot that it can produce the required D level of pathogen reduction nearly instantaneously. This impractically high temperature invariably leads to overcooked meat and vegetables while preventing very few cases of foodborne infection in addition to those that would be prevented by less extreme heat. After all, once a pathogen is dead, heating it further doesn't make it any deader."

    It's a complicated subject, and I'm not going to quote the entire chapter of the book, but if you're willing to research the topic, you'll be able to make juicier, tastier food by cooking to a lower internal temperature, and it will be just as safe of pathogens as if you were to incinerate it per the oversimplified USDA and FDA guidelines.  

    I'll try to take some pictures of the graphs / charts in there, as I'd think excerpts should be allowable under fair use.  If you're into sous-vide, gastronomy, or are at all interested in the hows and whys of food texture, you owe it to yourself to invest in the books.  Or at the very least, befriend someone who's dropped the coin on them...
     
  18. Glad to see the discussion since I'm a big sous vide fan as well as a fellow smoker.  I built my own and then bought a Sous Vide Supreme.  There's nothing like taking rib eyes out of the freezer, throwing them in the sous vide at 131 degrees for about an hour, and then searing them on a hot grill.  I have done many thick (greater than 3") roasts and I'll never do them any other way because  when they're done correctly, they are the perfect temperature and extremely tender.  I just did a sirloin tip roast last this weekend and made fantastic French dip sandwiches. 

    Regarding Ziploc bags, you might want to take a look at Doug Baldwin's videos - he actually demonstrates using both Ziploc and Foodsaver bags when cooking chicken breasts.  Personally, I use the Foodsaver type but if Doug is ok with Ziploc bags, they must be ok. 

    Great discussion guys!
     
  19. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    There is a lot of discussion on Pathogens, how common or rare they are and whether or not they are killed at 130*F. This is all good but we must consider that some of the most common Bacteria, given time, will produce Heat Stable Toxins or Spores. Heat stable meaning, no matter how hot or how long you heat them they will not degrade and will make you sick and spores can become active and multiply and/or produce toxin. Here is a great Chart laying out the Name of the bacteria and information related to our discussion...JJ
    [size=-1][size=-1]Bacteria
    Responsible[/size][/size]
    [size=-1]Description[/size][size=-1]Habitat[/size][size=-1]Types of
    Foods[/size]
    [size=-1]Symptoms[/size][size=-1]Cause[/size][size=-1]Temperture
    Sensitivity[/size]
    [size=-1]Staphylococcus aureus[/size][size=-1]Produces a heat-stable toxin[/size][size=-1]Nose and throat of 30 to 50 percent of healthy population; also skin and superficial wounds.[/size][size=-1]Meat and seafood salads, sandwich spreads and high salt foods.[/size][size=-1]Nausea, vomiting and diarrhea within 4 to 6 hours. No fever.[/size][size=-1]Poor personal hygiene and subsequent temperature abuse.[/size][size=-1]No growth below 40o F. Bacteria are destroyed by normal cooking but toxin is heat-stable.[/size]
    [size=-1]Salmonella[/size][size=-1]Produces an intestinal infection[/size][size=-1]Intestinal tracts of animals and man[/size][size=-1]High protein foods - meat; poultry, fish and eggs.[/size][size=-1]Diarrhea nausea, chills, vomiting and fever within 12 to 24 hours.[/size][size=-1]contamination of ready-to-eat foods, insufficient cooking and recontamination of cooked foods.[/size][size=-1]No growth below 40o F. Bacteria are destroyed by normal cooking.[/size]
    [size=-1]Clostridium perfringens[/size][size=-1]Produces a spore and prefers low oxygen atmosphere. Live cells must be ingested.[/size][size=-1]dust, soil and gastrointestinal tracts of animals and man.[/size][size=-1]Meat and poultry dishes, sauces and gravies.[/size][size=-1]Cramps and diarrhea within 12 to 24 hours. No vomiting or fever.[/size][size=-1]Improper temperature control of hot foods, and recontamination.[/size][size=-1]No growth below 40o degrees F. Bacteria are killed by normal cooking but a heat-stable spore can survive.[/size]
    [size=-1]Clostridium botulinum[/size][size=-1]Produces a spore and requires a low oxygen atmosphere. Produces a heat-sensitive toxin.[/size][size=-1]Soils, plants, marine sediments and fish.[/size][size=-1]Home-canned foods.[/size][size=-1]Blurred vision, respiratory distress and possible DEATH.[/size][size=-1]Improper methods of home-processing foods.[/size][size=-1]Type E and Type B can grow at 38o F. Bacteria destroyed by cooking and the toxin is destroyed by boiling for 5 to 10 minutes. Heat-resistant spore can survive.[/size]
    [size=-1]Vibrio parahaemolyticus[/size][size=-1]Requires salt for growth.[/size][size=-1]Fish and shellfish[/size][size=-1]Raw and cooked seafood.[/size][size=-1]Diarrhea, cramps, vomiting, headache and fever within 12 to 24 hours.[/size][size=-1]Recontamination of cooked foods or eating raw seafood.[/size][size=-1]No growth below 40o F. Bacteria killed by normal cooking.[/size]
    [size=-1]Bacillus cereus[/size][size=-1]Produces a spore and grows in normal oxygen atmosphere.[/size][size=-1]soil, dust and spices.[/size][size=-1]Starchy food.[/size][size=-1]Mild case of diarrhea and some nausea within 12 to 24 hours.[/size][size=-1]Improper holding and stroage temperatures after cooking.[/size][size=-1]No growth below 40o F. Bacteria killed by normal cooking, but heat-resistant spore can survive.[/size]
    [size=-1]Listeria monocytogenes[/size][size=-1]Survives adverse conditions for long time periods.[/size][size=-1]Soil, vegetation and water. Can survive for long periods in soil and plant materials.[/size][size=-1]Milk, soft cheeses, vegetables fertilized with manure.[/size][size=-1]Mimics meningitis. Immuno- compromised individuals most susceptible.[/size][size=-1]Contaminated raw products.[/size][size=-1]Grows at refrigeration (38-40o F.) temperatures. May survive minimum pasturization tempertures (161o F. for 15 seconds.)[/size]
    [size=-1]Campylobacter jejuni[/size][size=-1]Oxygen sensitive, does not grow below 86o F.[/size][size=-1]Animal reservoirs and foods of animal origin.[/size][size=-1]Meat, poulty, milk, and mushrooms.[/size][size=-1]Diarrhea, abdomianl cramps and nausea.[/size][size=-1]Improper pasteuriztion or cooking. cross-contamination.[/size][size=-1]Sensitive to drying or freezing. Survives in milk and water at 39 o F for several weeks.[/size]
    [size=-1]Versinia enterocolitica[/size][size=-1]Not frequent cause of human infection.[/size][size=-1]Poultry, beef, swine. Isolated only in human pathogen.[/size][size=-1]Milk, tofu, and pork.[/size][size=-1]Diarrhea, abdominal pain, vomiting. Mimics appendicitis.[/size][size=-1]Improper cooking. Cross-contamination.[/size][size=-1]Grows at refrigeration temperatures (35-40o F.) Sensitive to heat (122 oF.)[/size]
    [size=-1]Enteropathogenic E. coli[/size][size=-1]Can produce toxins that are heat stable and others that are heat-sensitive.[/size][size=-1]Feces of infected humans.[/size][size=-1]Meat and cheeses.[/size][size=-1]Diarrhea, abdominal cramps, no fever.[/size][size=-1]Inadequate cooking. Recontamination of cooked product.[/size][size=-1]Organisms can be controlled by heating. Can grow at refrigeration temperatures.[/size]
     

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