I have not yet seen such functionality in SAP.
You would at least need to declare the cold room as a separate storage location and then do transfer posting to another storage location if you remove something from the cold room and another movement if you put it back later.
If your users are posting just-in-time then you can derive the time to be reduced from the difference of the CPU time of the 2 movements and can update the Shelf life with a BAPI. The difficulty would be to know which two 311 movements belong together.
Alternative you may create a new transaction with its own dynpro where the user can enter material, plant, batch and the time where the material was not in the cold room and then the BAPI can reduce the shelf life. But you have to care about that you don't record the time multiple times, so you need some reference for your time recording.