First Brisket Attempt

JeffCowley

I'm attempting my first brisket this weekend.  I was able to buy a 7.5pound flat from my local grocery store and coated it with regular yellow mustard and John Henry's Raspberry Chipotle Rub.  

I started the lump at 11pm and finally put the meat on at 1:35am.  I had some issues in between and was forced to re-light the lump.  I put the meat on when the digiQ was reading a steady 225-240 degrees.  I'm concerned that my digiQ isn't reading accurately.  I've cooked several times previously with the digiQ and it always seems to run much hotter than the metal thermo inserted in the dome (the one installed from the factory/dealer).  Here is a detail of the temperature differences between the digiQ and the dome thermo so far:

1:00am 326 digiQ 280 dome

2:00am 250 digiQ 220 dome

3:00am 235 digiQ 200 dome

5:00am  240 digiQ 150 dome

7:00am 236 digiQ 150 dome

How concerned should I be?  Should I be concerned at all?  Until I started using the digiQ I had no reason to suspect the dome thermo was wildly inaccurate.  I'm worried that I'm practically cold smoking this brisket.  Dinner is planned for this afternoon/evening, so I suppose I have the time for a 18hour cook.  However, I was only planning on around 12.

Any ideas?  Suggestions?  Similar findings when using a digiQ?

Shiff

Have you calibrated your dome thermometer?

A 7.5 pound flat should take about 10 hours to cook using conventional brisket techniques.  A flat is a very difficult brisket to cook by normal means which is why many here use the Travis method which cooks it in liquid so it doesn't dry out.  A packer brisket has a flat and point which is much more forgiving of problems.

I'd probably foil the flat when it reaches the stall ( internal temp of 150-160) and then uncover it for a while at the end.

JeffCowley

Thanks for the advice.  The 9:00am reading is an even bigger disparity -- digiQ at 280 and dome thermo at 160.  The food probe is reading 157, so I think its fair to say I've entered the stall.  I'll take your advice and cover for awhile.

sumoconnell

Jeff, I suspect the dome thermo based on what you just posted.. no way you are at 157it, with dome at 160...

sumoconnell

Is the dome then touching the brisket?

JeffCowley

Sumo - I hadn't thought about it that way, but I suppose that's right.  I'm going solely by the digiQ this time around and we'll see what happens.  Thanks for the advice!

Mattman3969

If you don't have the retainer clip on your dome thermo you could pull it and calibrate in boiling water. Might help ease your mind.