What lends certain wines that "peppery" taste?

[wineguruchgo]

Under US Law, the grape varietal on the label must be 75% of what it says it is. The other "hidden" 25% can be whatever they want and they don't have to tell you.

If this was a purchase off the store shelf I would guess that they added Zin or Syrah to it and wasn't telling you.

I would like to think that someone from a winery would know the "exact" blend. But then again, maybe not. This might be a case of someone at the winery having a summer job and not knowing enough about wine to actually ask if it was 100% merlot.

That's my guess.