Can I refrigerate pre-wrapped beef in its original packaging ?

Yes. In fact, it is recommended. Food scientist Susan Brewer, Ph.D., explains why:  “In the U.S., most 
red meat and poultry in the retail case is packaged in modified atmosphere packaging, which is high in
carbon dioxide.  The purpose of the CO2 is to suppress microbial growth.  If you unwrap the meat, you
lose this protection.  In addition, every time you handle the meat, it becomes contaminated by air,
hands, and contact surfaces."
 
Source(s):
Brewer, M.S. and Chapman-Novakofski, K. 2006.  Meat Safety for the Consumer, University of Illinois Extension.