First brisket. It went in Friday evening at 135°F (57°C) because I want the sliceable kind rather than the pulled kind, and the plan was 48 hours, out Sunday night. It is now Saturday evening and I have hit the stage of the cook where you have nothing to do but think.
Three things I can't settle. One, is the second 24 hours actually earning its keep, or is a brisket basically as tender as it's going to get after a day and I'm just running the electricity for nothing. Two, when I checked this morning the water was down about two inches and the top corner of the bag was NOT under water, no idea for how long, possibly all night. Three, and this is the one keeping me up, is two whole days sitting at 135 actually fine? That number is a lot lower than anything I have ever left on a counter for five minutes without being told off.
Talk me through it before I panic-crank the temperature.
Hours 25 to 48 are absolutely doing something, they're just doing it slowly and invisibly, which is the worst combination for a first timer's nerves.
At 135 the collagen conversion is genuinely slow. Pull that brisket at 24 hours and you'd get something that slices but fights you a bit. At 48 it slices like a very good steak and the fibres let go properly. Push on to 60 and you start creeping toward the point where slices stop holding together, which is a different failure to the one you're worried about. My own rule after a lot of these: 135 gets the full two days, 155 gets about a day, and I don't cook a brisket at either temperature on a weeknight because I like sleeping.
The exposed corner I'd worry about more than the clock. Sort that out and stop watching the pot.
Two inches overnight sounds about right for an uncovered container and it is exactly how I ruined a pork shoulder before I learned. Cling film across the top, or a lid with a notch cut for the circulator, or the ping pong ball thing if you like looking ridiculous. Any of the three basically eliminates it.
#4August 3, 2026, 11:48 am Taking your three questions in the order they actually matter, because they are not equally urgent.
Safety first, since that's the one that sounds alarming and is genuinely the least of your problems. 135°F (57°C) sits above the danger zone, which runs from 40 to 140°F (4 to 60°C) in the sense that matters here, and above the roughly 130°F (54.4°C) line below which extended holds are not appropriate. A brisket held at 135 for two days is pasteurised many times over long before the second day starts, because pasteurisation is a time and temperature pair and you have given it an enormous amount of both. What you must not do is decide from this that a 129°F hold for two days is the same kind of fine. It is not, and the gap between those two numbers is the whole argument.
Second, the exposed corner. That is the real issue in your post. Meat above the water line is not at 135, it is at whatever the air above your kitchen counter is, and if that corner sat out most of the night it spent hours in exactly the range you were right to be nervous about. If it was a small corner of an otherwise submerged bag, and the meat there was still hot to the touch and in contact with the water below it, I would carry on. If a real portion of the meat was sitting dry and cool, I would not serve it. That is a judgement about your specific bag that I cannot make from here, so make it honestly rather than hopefully.
Third, the boring answer to your actual question: yes, hours 25 to 48 are working. Mike's numbers match mine. Cover the bath, top it up with hot water, and the whole thing looks after itself. The brisket guide has the temperature and time ranges laid out, and it explains why the sliceable range starts at 135 rather than lower.
New here and mostly reading, but "the gap between those two numbers is the whole argument" is going on my fridge next to the steak note. I had genuinely assumed the danger zone was a vibe rather than a line.
For what it's worth I check my long cooks the way I check on a sleeping toddler: once before bed, once in the morning, hot water in the jug, no drama. It stopped feeling like an event about the third time I did it.
Update, and it's a good one. Corner was small and still warm and the meat under it was clearly at temperature, so I carried on. Out at 48 hours, dried hard, twelve minutes in a very hot oven for the crust, and it sliced like something I'd pay for. Kids ate it, which is the only review I trust.
Foil went on the container at 9am Sunday and the water level barely moved after that. Next one goes in with the cover on from minute one.
