The Collaborative International Dictionary of English v.0.48:

Beef \Beef\ (b[=e]f), a.
   Of, pertaining to, or resembling, beef.
   [1913 Webster]

   Beef tea, essence of beef, or strong beef broth.
      [1913 Webster]

WordNet (r) 3.0 (2006):

beef tea
    n 1: an extract of beef (given to people who are ill) [syn:
         beef tea, Bovril]