From our Q & A here:
WHAT ARE THE PROS AND CONS OF AGING TENDERLOIN?
When you dry age meat a couple of things happen–the enzymatic activity softens the texture and the moisture loss deepens the flavor. In the case of a tenderloin, because the texture is already tender (thus the name) aging does not improve the texture. In fact, it can make the texture too soft or mealy. Furthermore, since the tenderloin has a large surface area, you will have cut off the entire outer surface. This is a tremendous trim loss on a particularly expensive and precious cut of beef..
It is especially important that you do not try to cover the meat with fat and age because there will be no surface air for the moisture exchange and the meat will simply rot. That has been our experience.
The flavor of the tenderloin can be improved with aging for only a few days before the surface darkens and hardens. This way you deepen the beefy flavor without the trim loss and risk of damaging the texture.
UMAi Dry® now offers a special Tenderloin Kit for this purpose.