50 hour brisket drop in temperature

I am new to Sous Vide. I am cooking a brisket using the recipe from the app that called for 50 hours. I had checked the water level before going to bed and again around 4 this morning. Added water before bed but not at 4. When I got up at 9 it was beeping. The temp was at 101. I am okay to just add water and keep going or get rid of it and start again?

How long had it cooked before you checked it last? Was the beeping due to low water, or was there another issue?

The beeping was low water. I had checked it at 4 am so 5 hours. The temp was at 101

How long had it been cooking at 4 am?

Ottleyfam, congratulations, you are one very brave new SV cook. Brisket is one of the most challenging pieces of meat to cook using any technique.

That’s the 135F x 50 hour cook app, right?
At 135F there should not be significant evaporation, however on long cooks seasoned users often employ some method of covering their vessel to minimize water loss.

You will learn as you progress in SV cooking that the technique imposes a disciplined attention to detail in your cooking.

There’s a few details missing that would help diagnose your problem.
The thickness of your brisket. Whole, or a piece of brisket?
Start time of cooking at 135F.
Size of your water bath.
Water level at commencement of cooking and when checked. MIN, MAX, or somewhere in between?

You don’t disclose your start time so it’s hard to know what degree of heat diffusion had been achieved in your brisket of unknown thickness. You tell us water level and temperature were satisfactory at 0400. Correct?

We know as a rough approximation that heat penetrates meat at the rate of 1-inch per hour. The thicker the meat the slower the heat penetration. Then knowing the cooking time from start to 0400 and the thickness of the brisket will allow you to judge if heat had thoroughly penetrated the meat and if it was safe at 0900.

You might find it useful to do a 24-hour test cook at 135F with nothing but water. From that you will gain an understanding of water loss through evapoartion and the unit’s reliability.

Wow there is a lot to consider.
So I started the brisket at 10 on Friday morning. The brisket is 3 inches thick by 14 inches long and 10 inches wide.
The vessel is a Coleman cooler that is 13 inches by 7 inches by 17 inches with a water depth of 6 inches. The water level was just below the max by approximately 1/16 of an inch.
I hope that provides more information.
Thank you for your help

Since 10am on Friday

Ot, thank you for the information. You have have half a brisket, either the Flat or most likely the Point cut, doesn’t matter a lot in a very long cook.

Cooking started at 1000 Friday and continued until at least 0400 the following day, for 18 hours. We know that at 135F Pasteurization is achieved after about 5 hours in a 3-inch thick piece of meat. (Baldwin 2008, Table 5.1)

FYI, Pasteurization is the substantial reduction of the potentially harmful pathogens of Listeria, Salmonella, and E. Coli to the degree where they can no longer be considered harmful. Your meat was more than safe for consumption at that time.

Next we have to consider what happened sometime after 0400 to cause Anova to “beep”, and presumably stop operating during the next 5 hours. Was it the result of low water level? Most likely as that Colman cooler has 1 1/2 square feet of surface area which is a lot. We know that significant water loss occurred from 1000 to bedtime. Thus in future long duration cooks more water is likely needed to be added after similar durations of time if you don’t take steps to reduce evaporation such as floating plastic film, a cover, or ping pong balls.

Since the brisket was Pasteurized, and an intact cut of meat, and for personal use within the home only for people without a compromised immune system. I would have continued to cook the meat to completion as its core temperature would have remained higher than the water temperature.


1 Like

Thank you. That is what I did. I now know more for my next attempt. I am sure it will be the best tasting brisket I have had. Thank you all for the help.

1 Like

You’re wecome.

On long cooks you should take preventive steps to minimize evaporation.

You can buy a cheap bag of ping pong balls (usually sold for beer pong) and toss those on top. Really helps reduce evaporation.

If you already have the Coleman cooler, you must have the lid to it. Cut or drill a hole in the lid(I used a hole saw) that’s the same size as your SV. Fill the cooler to the proper level, put on lid, slide SV through the hole and you’re done. I have the same setup, but a larger cooler. I’ve done 50 hr. cooks without having to add more H2O. I drilled the hole in a corner for good circulation.