How long to Sous Vide a roast?

[just4fn]

I did a 8 lb roast a couple of weeks ago on the Kamado and it came out very good.  It just was not as tender as I would like.  I am going to try and sous-vide it next time.  How many hours would you suggest?  I did a brisket at 50 hours but that is a different animal.  The roast is like a top round.  I'm thinking 20 hours at 125.  What do you gurus think?

[m-fine]

I think anything under 130 degrees risks not pasteurizating it completely so my minimum cook temp on a long cook would be 131. The more tender the meat is at the start, the less time you need, so I would go closer to 8-12 hours. 

[John Setzler]

1 hour ago, m-fine said:

I think anything under 130 degrees risks not pasteurizating it completely so my minimum cook temp on a long cook would be 131. The more tender the meat is at the start, the less time you need, so I would go closer to 8-12 hours. 

 

It will pasteurize at 130.  It just takes time.  The meat just needs to be held at 130 for about 2.5 hours.  

[John Setzler]

19 hours ago, just4fn said:

I did a 8 lb roast a couple of weeks ago on the Kamado and it came out very good.  It just was not as tender as I would like.  I am going to try and sous-vide it next time.  How many hours would you suggest?  I did a brisket at 50 hours but that is a different animal.  The roast is like a top round.  I'm thinking 20 hours at 125.  What do you gurus think?

 

What kind of roast was it?

 

[m-fine]

36 minutes ago, John Setzler said:

 

It will pasteurize at 130.  It just takes time.  The meat just needs to be held at 130 for about 2.5 hours.  

 

He said 125 in the original post, which I believe is unsafe*.  I add the extra degree to 130 because the internal temp of the meat lags the water temp even after several hours, and as a margin of safety for accuracy of the device. 

 

* I have looked for reliable sources on food safety (Government and University research etc.) and have not found anything that says a temp below 130 is safe or how long it takes to pastuerize at those temps.  Lack of data doesn’t mean 125 is dangerous, but I don’t want to be a food safety researcher when I cook food for human consumption, and I wouldn’t recommend it to others. 

[John Setzler]

4 hours ago, m-fine said:

 

He said 125 in the original post, which I believe is unsafe*.  I add the extra degree to 130 because the internal temp of the meat lags the water temp even after several hours, and as a margin of safety for accuracy of the device. 

 

* I have looked for reliable sources on food safety (Government and University research etc.) and have not found anything that says a temp below 130 is safe or how long it takes to pastuerize at those temps.  Lack of data doesn’t mean 125 is dangerous, but I don’t want to be a food safety researcher when I cook food for human consumption, and I wouldn’t recommend it to others. 

 

You don't need to worry about pasteurizing someting like a beef roast.  If we did, we could never eat rare steak or most medium rare steak.

 

 

[just4fn]

7 hours ago, John Setzler said:

 

What kind of roast was it?

 

It was the peeled knuckle. I am going to try it again sous vide style

[m-fine]

3 hours ago, John Setzler said:

 

You don't need to worry about pasteurizing someting like a beef roast.  If we did, we could never eat rare steak or most medium rare steak.

 

 

I cannot agree with that at all. Rare steak is not held in an anaerobic environment within the “danger zone” temperature range for many hours.  Once you vacuum bag it and extend the cook time, the situation changes. 

 

Sous Vide done wrong is a perfect environment for botulism so caution is necessary. 

[John Setzler]

1 hour ago, m-fine said:

I cannot agree with that at all. Rare steak is not held in an anaerobic environment within the “danger zone” temperature range for many hours.  Once you vacuum bag it and extend the cook time, the situation changes. 

 

Sous Vide done wrong is a perfect environment for botulism so caution is necessary. 

 

I will step out of this conversation.  I have spent too much time researching what is and isn't safe with sous vide.  Whatever works for you is good.

[BURGER MEISTER]

Like mushrooms, they're all are edible.....once.    Sous vide is all safe......once.

[m-fine]

1 hour ago, John Setzler said:

 

I will step out of this conversation.  I have spent too much time researching what is and isn't safe with sous vide.  Whatever works for you is good.

 

If your research found a source that says cooking at 125 for more than 4 hours is safe, please share it. I am always looking to learn more and I welcome any data you have. So far everything I have found says either keep the time below 4 hours (or less) or keep the temp above 130, but I certainly haven’t read everything out there. 

[m-fine]

2 hours ago, BURGER MEISTER said:

Like mushrooms, they're all are edible.....once.    Sous vide is all safe......once.

 

Sous Vide is precise, and mostly  consistent and repeatable so it is easy enough for those with the proper tools to test the impact of time and temperature on bacteria populations and for the rest of us to follow their guidelines to stay safe.  I have a lot more confidence in my ability to read a temperature setting and set a timer correctly than I do in my ability to properly identify a wild fungus. 

 

That said, my confidence goes to zero when outside the range of published data tables. 

 

[m-fine]

Here are some quick hit sources...

 

this is is not academic, but note the first warning is to keep the time below a few hours or the temp above 130. Also note that he says the bacteria thrives up to 126. 

https://www.amazingfoodmadeeasy.com/info/exploring-sous-vide-email-course/more/is-sous-vide-safe-key-safety-guidelines

 

Doug Baldwin:

”If the food is not being pasteurized (as is the case with fish and rare meat), it is important that the food come up to temperature and be served within four hours.”  He has pasteurization tables, formulas used, and cited sources. 

http://www.douglasbaldwin.com/sous-vide.html#Cooking

 

USDA guidelines. Note the tables start at 130

https://www.fsis.usda.gov/OPPDE/rdad/FRPubs/97-013P/COMPLIANCE GUIDELINES FOR RTE MEAT AND POULTRY.doc

 

 

 

[fbov]

20 hours ago, m-fine said:

... USDA guidelines. Note the tables start at 130

https://www.fsis.usda.gov/OPPDE/rdad/FRPubs/97-013P/COMPLIANCE GUIDELINES FOR RTE MEAT AND POULTRY.doc

I went looking for this document, and it's not available through links at the USDA web site. If you follow the URL, it's all Error 404 Forbidden sites. This is NOT A GUIDELINE, but an internal document not meant for public distribution. Take the header warning very seriously:

THIS DOCUMENT IS A DRAFT AND SHOULD NOT BE USED FOR REGULATORY ENFORCEMENT OR COMPLIANCE PURPOSES

 

Now, it's quite possible the data is good and it's some other bureaucratic issue is blocking publication, but who knows? I think a grain of salt is warranted...

 

HAve fun,

Frank

[cschaaf]

FWIW The Joule app shows temp/time setting for ribeye roast as low as 122 degrees. Time is anywhere from 3 - 6 hours (for fresh, not frozen) depending on the diameter of the roast (4 - 6 inches).