OK... Step away from the brisket :-D
Deep, calming breaths :becky:
Could you slice the brisket and it was tough, or was it falling apart? If you could slice it and it was tough, then it was under cooked. If it was falling apart, then it was over cooked.
You said that you pulled it when it probed 203. It is entirely possible that it wasn’t done at 203, especially with a 275 degree smoker temp.
Here is what I do...
Cook at 300 on the grate until the back color is where I like it (about 2 hours, typically)
Wrap and cook at 250 until the thickest part of the flat is probe tender. (About another 2 - 2 1/2 hours typically) I start probing at 2 hours.
Open the foil and vent for 10 minutes
Close the foil and put into the Cambro to rest.
I can’t remember the last time that I used the internal temp of a brisket or butt to determine the timeline. Each piece of meat is different, and the cook temp will also make a difference. I use my Thermapen as my probe since it is always what I use, and I can tell you that the IT will be 210 and even higher when the brisket is tender most of the time.
^^^^^ this.
A couple of points to somewhat extend what Ron (and others) said.
Tenderness of a brisket comes with the breaking down of the connective tissue between the muscle fibers. Luckily for us all, this is also where the moisture of a brisket comes from. Those connective tissues get broken down and the collagen renders. However, if cooked too long, that newly released rendered collagen will cook out and your brisket will get dry again.
WRT finished internal temp. There's a number of factors that determines what that finish temp will be. One of those factors is chamber temp. The breaking down of the connective tissue is a function of temperature over time, or time at temp. As you cook it , the brisket will spend different amounts of time at various temps. Like it might be between 40 and 50 degrees for 1 hour. Between 50 and 60 for 50 minutes, 60 and 70 for 40 mins. (BTW< I made these numbers up just to illustrate the point). As the internal temp increases, the rate of breakdown increases as well, shortening the overall cook time.
If you cook at a higher chamber temp, the brisket runs through each of those temp ranges much faster. The inevitable result is that the higher the chamber temp, the higher the finished Internal temp will be.
So, say you have 3 identical choice grade briskets. Exact clones of each other. One cooked at 225 will have lower finish IT than one cooked at 300. One cooked at 275 will have a finish IT in between those two.
Grade of beef also factors in. Usually, I believe Prime will have a lower finish IT. Choice would be in the middle. Select grade would be the highest.
To further complicate matters, let's go back to chamber temp. Most folks aren't using thermostatically controlled insulated ovens to cook brisket. Those types of cookers hold absolutely steady and consistent temps. Most smokers don't. You might target 250, but your smoker might settle in at 240 or 270. It might not (probably won't) even settle in. You might have temp swings of 20-40 degrees or whatever. It's no big deal, but that variation in temp quite possibly might affect what your finish IT will be.
On "probing". Packer briskets have two parts, the flat and the point. These are two different muscles and they have different characteristics. The point has a looser grain, more intramuscular fat and less connective tissue. The flat is a deeper pectoral muscle that does more work. It has less internal fat, a tighter muscle structure and more connective tissue.
When it comes time to probe, you can, and should, completely ignore the point. Due to having less connective tissue, it will be "done" and tender before the flat. But, due to it's higher fat content, it can cook for longer without over cooking. It's because of this that when the brisket is "done", you can pull it, separate off the point, cube it up, sauce it and put it back on the smoker for another hour or more to make unctuous burnt ends. It's actually kind of difficult to really overcook a point.
The flat is what you want to pay attention to. Specifically, the thickest part of JUST the flat. While your brisket is raw and trimmed, examine it. See where the point and the flat meet. Notice the seam of fat that separates them. Try to identify the rough area where it's just the flat and find the thickest part. Once bark is developed, it'll be a bit more difficult to figure it out.
Anyways, at about 185ish (doesn't matter if it's wrapped or not), start probing around the thickest part of the flat. Here is where experience will really kick in. The first couple times, I'd probably probe it every 15 to 20 mins. Nothing elaborate, just open the smoker, stab a few times, close the smoker. Once you have some experience under your belt, you might be able to adjust those times. Like, if it feels really tough to probe, you could probably give it another hour before probing again. The frequency of when to check will depend on how the brisket feels. Like, if it's close, but not quite there, maybe give it another 10 mins. But, to start out, I'd go with a set schedule.
Anyways, that's some of the reasoning/rationale behind it all. I've found that for me at least, understanding what is going on and why has let to more success with my cooking.
Sorry for the long dissertation. My ADD is apparently running unchecked today
