Rack of lamb

I have three questions.  First, I have seen different temps and time for rack of lamb: 135 for 1 hour, 134 for 2 hours, 130 for 2 hours, etc. What is recommended for medium rare?

Second question concerns the size of the container.  I need to cook four racks but container will be crowded. How much circulation room should be left around food.

Third, what is the maximum size container that can be used:

Many thanks. 

I have seen a video where 2 racks of lamb were bagged together with the bare rib bones overlapping and 4 racks fit fine in a 6 lire stockpot.

Many people use large coolers (I think insulated can be larger)./

I have not done a rack but have done quite a few loin lamb chops. I like 135 for 1  1/2 to two hours for a 1 inch thick chop. Hard to explain but there is a definite taste and texture difference. Always delicious though, hard to go wrong with lamb IMO.


AFAIK circulation space is not critical.  Some expensive sous vide equipment do not have a circulator. More circulation is better I am sure but I wouldn't stress about it.

I will go out on a limb and say 134 degrees for 2 hours. Someone else may know better:)

Thanks for the comments.  Dinner party preceded getting your response so i went ahead with 3 racks (rather than 4) and at 132 for 2 hours in a 4.75G Cambio container.  In the future, I would set temp at 134 since lamb verged on rare. Also, would recommend that all fat be trimmed from the racks: searing would be faster and makes for a better looking presentation.  I like the idea of bagging racks together – can see how that might work.

Thanks again.

Thanks for letting us know.

It is all trial and error for me and sometimes I don't like what the majority does. but often I do. I find I like sous vide meat slightly more done than with conventionally cooked. Would have bet big bucks against that at one time.

@Helen I tend to agree although it is not a great increase in temperature for me. For steaks and roasts I have settled on 132°-134° F instead of where I began at 130° F for beef.