I have been cooking sous vide a lot lately and tonight I was wondering if I really need to let my 3ld tri-tip rest 15-20 min before slicing or can I let it rest for a shorter amount of time?
PS it has been a while ;)
resting is based upon the temperature differential between 'cooked' and cooking temp. It mainly pertains to hold-over cooking and stabilizing.
When cooking sous-vide the differential is not noticeable.
Cook and get your plates ready then slice!
Some people say yes, that resting the meat will allow it to re-absorb some of the juices that are in the bag back into the meat. Others say not to bother, the temperature difference isn't enough. I'd say not to worry about it. Maybe give it a minute or two before you slice, after you sear in the pan, but it probably isn't necessary.
You could do an experiment for us--sous vide 2 identical cuts in different bags, cook them sous vide at the same time, but rest one and not the other. See if you can tell.