I often Sous Vide something & then put it in the refrigerator for several days (in the vacuum sealed bag it was Sous Vide in)
QUESTION is:
Do I have to bring that item back up to the temperature it was Sous Vide in before I can sear it?
Would your answer be different if I am going to sear it under the broiler (An example would be a roast.)
No, I do not believe that a piece must in general be warmed for searing.
A thick piece, a thick steak or roast can be seared with little effect on the interior due to the limited heat transfer rate of protein. A thin quality piece’s only heating for cooking and presentation might be due to the sear.
The objective of searing is to heat the surface to induce the Maillard reaction, about 300ºF, without further heating the interior.
Perhaps best to bring the package back to a few degrees below the original target temperature, then remove from the sous vide bag, blot with absorbent kitchen paper to dry the surface.
It’s now ready for your preferred searing method and should take just a few minutes and with no risk of cold or overcooked meat.