140 Rule

Discussion in 'Pork' started by mabrandt, Jun 21, 2014.

  1. mabrandt

    mabrandt Fire Starter

    Was smoking a 7lb butt today. Put it on at 5am and at 9am, the IT was only 110. The outer layer with the instant thermometer read 130. Smoker temp was 230 the entire time. From what I have read and been told, I tossed the butt. I don't think I ever had this trouble before, but it also could have been I never noticed the discrepancy before. I have smoked a lot of pork and never got sick, but perhaps I'm lucky. After throwing it away, I searched here and everyone seems to agree about the 40-140 in 4hrs to be safe. In searching the web, I found a lot of places that say it really doesn't matter as long as the smoker temp is at least 225 the entire time. I actually saw an email from a USDA official stating this fact and a link to the USDA web site here that says the same:


    I am going to do another tomorrow and will just start at 250 and keep it there to be safe, but if you think about it, a 10lb picnic roast in there at 225, no way 140 in 4 hours.I am curious on others opinions and how they would have handled it.

    Last edited: Jun 21, 2014
  2. noboundaries

    noboundaries Smoking Guru OTBS Member SMF Premier Member

    Hmmm, 110 IT after four hours.  That's pretty low.  Assuming you didn't inject the pork you can avoid the discard issues by not inserting your sterilized food probe until later in the smoke.  I also let my food probe rest in the smoker, heating up to 225F, 250F, 275F, whatever temp I'm smoking at before inserting it.  It sears the meat internally when I insert it.  Don't know if it actually helps or not from a safety point but makes sense to me.       
  3. venture

    venture Smoking Guru OTBS Member

    Chef Jimmy is your best bet on this one. Maybe drop him a PM?

    Did you inject?  Was it deboned?  Was anything else done to remove it from the "intact muscle meat" state?

    At what point in the process did you first insert a therm probe?

    Good luck and good smoking.
  4. mabrandt

    mabrandt Fire Starter

    No injection. Not deboned. Nothing out of the ordinary that I haven't always done. My maverick probe was put in the cold meat before I put it in the smoker, just like I always do. I doubled checked the temp with an instant read, so I know the maverick was correct. The only thing I can think of that I did a little different is the cabinet temp probe was mounted in the top shelf, not on the same shelf as the meat. Usually I have them on the same shelf. Is it possible that the meat was at a lower temp due to being lower in the cabinet? I have a Smoke Vault. The larger one.
    Last edited: Jun 21, 2014
  5. dirtsailor2003

    dirtsailor2003 Smoking Guru OTBS Member

    Yes you can have temp differences. In my GOSM which is similar to your smoke vault, I can have 15-20 differences from top to bottom. I always put my temp prob right on the rack that I am smoking on.
  6. mabrandt

    mabrandt Fire Starter

    That probably explains it then. 20 degrees difference makes a big difference. I bought another butt today. Will fire it up in the morning. Hopefully I can get it correct this time. Pure laziness on my part. I mounted the probe the night before in the top rack and when the butt didn't fit, I just put it on the lower rack. It didn't help that out of my basement fridge the it was only 38. Lesson learned. 
  7. venture

    venture Smoking Guru OTBS Member

    Inserting the therm probe in the cold meat transferred germs from the outside surface into the center of the meat.  This is no longer considered "intact muscle meat".

    Please PM Chef Jimmy.

    Good luck and good smoking.
  8. mabrandt

    mabrandt Fire Starter

    Well I'm 3 hours into the smoke and already hit the magic 140. I am assuming yesterday's trouble was due to the lower shelf being much cooler than where I was measuring it. I forgot that heat rises. LOL.  This knowledge will come in handy when I'm doing my sausage. Since I got the smoke vault, I had been having trouble with the flame going out at the low temperatures required if there was any wind what so ever. Next batch I'll try putting them on a lower shelf and see what happens. 

    Lesson learned. 
  9. chef jimmyj

    chef jimmyj Smoking Guru Staff Member Moderator Group Lead OTBS Member

    The 40 to 140 in  4 rule only applies to meat that is no longer intact muscle. So if it's not ground meat, no injection, bone in and only the probe puncture, you would have been fine. As far as putting the probe in cold, there is a risk but if the Butt had at least a Salt and Sugar rub applied, the risk goes down. It is always better to wait for the outer surface to get hot. Some wait hours before inserting the probe but the bacteria on the surface are killed very quickly just being exposed to 225°F. The easiest method to sterilize the probe site is to hit the probe point with a torch or even a heated spoon or any hot metal. Or wait an hour and insert the probe. If you have any questions about the " Rule ", read the info that is in the Safety Forum. It is all explained...JJ
    Last edited: Jun 22, 2014
  10. dirtsailor2003

    dirtsailor2003 Smoking Guru OTBS Member

    For your sausage definitely like into a needle cable modification. Also make sure you aren't in a windy area. If you are rig some wind breaks. If you are using cure in your sausage mix there is no need to start off with a high temp. At 180* and above you'll start rendering the fat and that won't make for a good sausage. Those using cure will start low like 100* (impossible to achieve with my GOSM on a good day no wind with the needle valve I can get as low as 125-130) then ramp the temp up 10-20 degrees every hour until the proper IT of the sausage is reached.
  11. eman

    eman Smoking Guru Staff Member Moderator OTBS Member

    For fine flame control get a needle valve regulator. You still may need a windbreak but the needle vale gives you much more control for a lower flame 
  12. mabrandt

    mabrandt Fire Starter

    Yes, I have the needle valve. Usually have no trouble starting at the low temps and ramping it up. Just when there is wind. I try and stay out of it, but sometimes it still goes out. Getting to the low temp was why I bought the smoke vault. The GOSM I had, had real trouble getting the temp down. 
    Last edited: Jun 22, 2014

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