Which Brahma beer is unhopped? I had a bottle of Brahma beer when I was in Brasíl some years ago, and I didn't save the label.  These are what I remember:


it was sweet and malty.
it had a white label.
it had 4% or thereabouts alcohol.
I purchased it at a decent and reputable restaurant circa 2008 — so it most probably wasn't an old or even a mislabeled bottle.


Reading their website is difficult for me, but I don't see anything which strikes me as a clear match — not even the Weiss (White) variety.  Possibly, I suppose, but I don't see anything in the description here which would obviate this question.
Are you sure it wasn't the Brahma Malzbier? I've had regular Brahma before and it taste like any other watery pale lager from MillBudCoors. 

The Malzbier is a beer that is dark and they add caramel and it's low alcohol and sweet.

http://www.brahma.com.br/cervejas/malzbier


  Manufacture: American pale lager type beer in which, after filtration, caramel and sugar syrup are added, giving the dark coloration and sweet taste.