Mackay's Epic Single Malt is a favored gift in Dragon Age: Origins - Awakening. It gives +10 approval (with diminishing returns) to Oghren, and +5 approval (with diminishing returns) for any other companion.
Dragon Age Origins - AwakeningEdit
Dragon Age: InquisitionEdit
See also EditGifts
Gifts can be sold to a merchant or given to certain party members to influence their approval rating.