Last night we enjoyed fantastic ribeye steaks, my third precision cook and thanks to my log, the little adjustments worked a treat. So I’m feeling a little more confident now and plan a 27 hour Sunday Roast for tomorrow evening. But I have been reading about long cooks stalling because of excess water evaporation and because of loss of heat from the container/bath. I have the clear 16L Anova container, which comes with a lid. Am I right to believe the lid will prevent evaporation to an extent that this long cook stalls? But will I have to insulate the container in some way or are the Anova clear containers grand for a 27hr 131F cook. And do I need to do it so long? When I google sous vide Roasts, some recipes are for as little as 5 hours.
The lid should eliminate excessive evaporation.
The time required depends on how tender the meat is to start with. This is one of the benefits of using the sous vide method. With a longer cook time you can turn a tough piece of met into. tender one. When looking up recipes I suggest entering the cut of meat for more accurate results.
Curlie, congratulations on those steaks and using your log. You are off to a great start.
We all should be well aware that separating fact from opinion on the internet can be challenging, - particularly these days. And in an election year it’s usually worse. One never knows what those pesky Russians are posting. That’s the value of your log where you may find it useful to record the change in water level for the longer cooks. Just so you know and can be prepared in the future.
Yes, the lid will substantially reduce evaporation. It becomes more of a problem with longer and higher temperature cooks. I check the water level about every 8 hours during 24-hour or longer cooks. Sometimes a top up is necessary. I also tumble the meat when inspecting the water level. It’s a habit i acquired when my vacuum packaging was sometimes sub-par. Doing that moves any bubbles that can reduce heat transfer.
Cook stalls is an unfamiliar term to me in SV cooking. As long as your circulator is functioning in adequate water heat continues to diffuse into the meat.
Insulation has no impact on the rate of evaporation as it is water temperature and surface area dependant. A lid allows evaporating water to condense and drop back into the water bath.
And do I need to do it so long?
Remember that challenge of sorting fact from opinion? If you feel confident following opinion do as you please. Using your log you’ll figure it after a while out based on the results of your experiences.
However, if you are more confident planning your cooks based on scientific fact based SV cooking you need to consider the undisclosed facts of your 27-Hour Sunday Roast.
Fact One: - the cut of meat. is it a tough cut or tender cut? Tough cuts require considerably longer cooking times than tender.
Fact Two: - thickness, the critical factor in determining SV cooking times. Please remember that. Any recipe that doesn’t provide thickness detail is an opinion or guess. At today’s meat prices i prefer not to trust a guess.
Fact Three: - your desired degree of doneness. We know that you want Medium-Rare because you selected 131ᴼF.
Many of us use Dr. Douglas Baldwin’s tables at the link below to determine thickness based cooking and chilling times. His work also covers about all you need to know about food safety.
Do well.
Thanks folks.
Stalling is a term normally associated with low and slow smoking of meats. It happens during the cook when the meat is releasing moisture and it cools the meat by evaporation. THis can not happen with sous vide.
Please don’t read too much into my use of the word stalling. Perhaps I should have said stopping because too much water evaporated from the water container, or slowing because the container didn’t retain the temperature.
You should have confidence in your Anova container’s heat retention capability. Similar foodservice products have been used successfully for over 40 years.
If you are cooking on a stone countertop there should be an insulating layer beneath the vessel to reduce heat loss and potential damage to your countertop. A folded bath towel will do.
Your concerns for stopping or slowing are a natural result of the substantial growth of absentee cooking contemporary circulators afford. Some Community members question the benefits considering the potential for loss. SV cooking may be something worth an occasional on site observation.
I hope your Sunday Roast is better than you expect.
One caution. Be sure to put an insulated mat of some sort under your cook setup, especially on stone or marble counter tops. The heat applied for so long might crack the counter as it did mine. A very small crack now, but I am watching it diligently.
I use a couple of flat silicone hot pads under the container and wrap the entire setup with the insulation I got with a Plated delivery. Works well.
Great heads-up Frank and Rick. I cooked on a marble top but will definitely be protecting it in future.
The roast was absolutely superb. Everyone loved it.
I ended up cooking at 133F for 10 hours and to be honest it was to lay down a marker, to improve on with future cooks but while the next one might be done for 12 hours, I wouldn’t change anything else.
Because of our isolating, no one was invited for dinner and we have plenty of leftovers, so looks like we have a couple of beef sandwich lunches to look forward to this week. 
I’m now fully committed to sous vide, so have just ordered a kitchen blow torch to help me with the sear in future.
Nice work Curlie.
If you get a similar roast next time you might want to split it in 2 pieces lengthwise along the visible seam and separately vacuum package them. Cook both together for your planned time, 10 or 12 hours. Two hours makes little difference in outcome. If you cook to Pasteurization you can enjoy one roast on cook day and store the other with packaging intact for a future meal after an ice bath deep chill. Chilling time = 1 hour per inch of thickness.
Reheat at cooking temperature according to thickness. Sear and enjoy.